updated docu for model migration
diff --git a/plugins/org.eclipse.app4mc.amalthea.converters.091/src/org/eclipse/app4mc/amalthea/converters091/impl/AbstractConverter.java b/plugins/org.eclipse.app4mc.amalthea.converters.091/src/org/eclipse/app4mc/amalthea/converters091/impl/AbstractConverter.java
index 66f7508..2afc9cd 100644
--- a/plugins/org.eclipse.app4mc.amalthea.converters.091/src/org/eclipse/app4mc/amalthea/converters091/impl/AbstractConverter.java
+++ b/plugins/org.eclipse.app4mc.amalthea.converters.091/src/org/eclipse/app4mc/amalthea/converters091/impl/AbstractConverter.java
@@ -15,19 +15,9 @@
 
 package org.eclipse.app4mc.amalthea.converters091.impl;
 
-import java.io.UnsupportedEncodingException;
-import java.net.URLEncoder;
-import java.nio.charset.StandardCharsets;
-import java.util.AbstractMap;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
-import java.util.Map.Entry;
-
 import org.apache.log4j.Logger;
 import org.eclipse.app4mc.amalthea.converters.common.base.IConverter;
 import org.eclipse.app4mc.amalthea.converters091.utils.HelperUtils_090_091;
-import org.jdom2.Element;
 
 public abstract class AbstractConverter implements IConverter {
 
diff --git a/plugins/org.eclipse.app4mc.amalthea.converters.help/docu/how_to_invoke_model_migration.textile b/plugins/org.eclipse.app4mc.amalthea.converters.help/docu/how_to_invoke_model_migration.textile
index 1e86158..cee2d51 100644
--- a/plugins/org.eclipse.app4mc.amalthea.converters.help/docu/how_to_invoke_model_migration.textile
+++ b/plugins/org.eclipse.app4mc.amalthea.converters.help/docu/how_to_invoke_model_migration.textile
@@ -25,7 +25,7 @@
 
 # Selected AMALTHEA model files : These are the models which are explicitly selected by the user
 # Model scope files : These are the model files which are referred in the models explicitly selected by the user <div>_Example:_ In the dialog shown above, mapping.amxmi is the file selected by the user, and it contains references to the model elements of : sw.amxmi, sw.amxmi-sw, default.amxmi-os. Due to this reason, all these referred models are selected implicitly for model migration <br/>*_Note:_* In case if the selected/referred models are having the different AMALTHEA model versions, migration can not be proceeded and the following error dialog is displayed <br/> !(gray_scale)../pictures/ui/different_model_versions.png! </div>
-# Input model version : This is the AMALTHEA model version to which both selected & referred models are belonging to <br/><div> *_Note:_* AMALTHEA model versions are represented with the following naming convention in this dialog<br/><table id="classic"><tr><td>AMALTHEA 1.0.3</td><td>itea.103</td></tr><tr><td>AMALTHEA4public 1.1.0</td><td>itea.110</td></tr><tr><td>AMALTHEA4public 1.1.1</td><td>itea.111</td></tr><tr><td>APP4MC 0.7.0</td><td>0.7.0</td></tr><tr><td>APP4MC 0.7.1</td><td>0.7.1</td></tr><tr><td>APP4MC 0.7.2</td><td>0.7.2</td></tr><tr><td>APP4MC 0.8.0</td><td>0.8.0</td></tr><tr><td>APP4MC 0.8.1</td><td>0.8.1</td></tr><tr><td>APP4MC 0.8.2</td><td>0.8.2</td></tr><tr><td>APP4MC 0.8.3</td><td>0.8.3</td></tr></table><br/></div>
+# Input model version : This is the AMALTHEA model version to which both selected & referred models are belonging to <br/><div> *_Note:_* AMALTHEA model versions are represented with the following naming convention in this dialog<br/><table id="classic"><tr><td>AMALTHEA 1.0.3</td><td>itea.103</td></tr><tr><td>AMALTHEA4public 1.1.0</td><td>itea.110</td></tr><tr><td>AMALTHEA4public 1.1.1</td><td>itea.111</td></tr><tr><td>APP4MC 0.7.0</td><td>0.7.0</td></tr><tr><td>APP4MC 0.7.1</td><td>0.7.1</td></tr><tr><td>APP4MC 0.7.2</td><td>0.7.2</td></tr><tr><td>APP4MC 0.8.0</td><td>0.8.0</td></tr><tr><td>APP4MC 0.8.1</td><td>0.8.1</td></tr><tr><td>APP4MC 0.8.2</td><td>0.8.2</td></tr><tr><td>APP4MC 0.8.3</td><td>0.8.3</td></tr><tr><td>APP4MC 0.9.0</td><td>0.9.0</td></tr></table><br/></div>
 # Output model version : This is the AMALTHEA model version to which both selected & referred models should be migrated to
 # Output directory : This is the location where migrated AMALTHEA models should be generated. <div>*_Note:_* <u>This option is available only if the specified output model version is 1.1.1 or higher.</u><br/> In case of AMALTHEA model versions 1.0.3 and 1.1.0 - &gt; Model scope is set as project, where as from version 1.1.1 and higher - &gt; model scope is limited to a folder. Due to this reason below is the behavior of model migration utility : <ul><li>If the output model version is selected as 1.1.1 or higher - &gt; <u>migrated models are generated in a single folder (due to scope restriction) specified by the user</u></li><li>If the output model version is selected as 1.1.0 - &gt; <u>input model files will be overwritten by the migrated model files</u></li></ul></div>
 
diff --git a/plugins/org.eclipse.app4mc.amalthea.converters.help/docu/meta_model_changes.textile b/plugins/org.eclipse.app4mc.amalthea.converters.help/docu/meta_model_changes.textile
index 7a24b3e..b86ab25 100644
--- a/plugins/org.eclipse.app4mc.amalthea.converters.help/docu/meta_model_changes.textile
+++ b/plugins/org.eclipse.app4mc.amalthea.converters.help/docu/meta_model_changes.textile
@@ -561,3 +561,17 @@
 |executingCore|Core|SchdulerAllocation|MappingModel|variable name is changed from executingCore to executingPU. Type is changed from Core to ProcessingUnit|
 |coreAffinity|Core|TaskAllocation|MappingModel|variable name is changed from coreAffinity to affinity. Type is changed from Core to ProcessingUnit|
 |items, runnableItems, computationItems|RunnableInstructions|Group, Runnable, Scheduler|SWModel, OSModel|Type is changed from RunnableInstructions to ExecutionNeed|
+
+h3. Version APP4MC 0.9.0 to APP4MC 0.9.1
+
+*Change in the namespace:* 
+
+table(classic){margin-left:40px}. 
+| *_AMALTHEA Namespace (version App4MC 0.9.0)_* | *_AMALTHEA Namespace  (version App4MC 0.9.1)_* |
+|http://app4mc.eclipse.org/amalthea/0.9.0 |http://app4mc.eclipse.org/amalthea/0.9.1 |
+
+*Below Classes are removed:*
+
+table(classic){margin-left:40px}. 
+| *_Class Name (version APP4MC 0.9.0)_* | *_Model Migration behavior_* |
+|TimeObject|Equivalent element of this class in 0.9.1 is Time |
diff --git a/plugins/org.eclipse.app4mc.amalthea.converters.help/docu/model_migration.textile b/plugins/org.eclipse.app4mc.amalthea.converters.help/docu/model_migration.textile
index b4ccfcf..7030a97 100644
--- a/plugins/org.eclipse.app4mc.amalthea.converters.help/docu/model_migration.textile
+++ b/plugins/org.eclipse.app4mc.amalthea.converters.help/docu/model_migration.textile
@@ -18,7 +18,7 @@
 
 For each release of AMALTHEA there will be changes in the meta model contents, due to this it is not possible to load models built from previous releases of AMALTHEA into latest tool distribution.
 
-*Model Migration functionality* is part of this distribution, using this feature it is possible to convert models from previous releases (e.g. itea.1.0.3, itea.1.1.0, itea.1.1.1, 0.7.0, 0.7.1, 0.7.2, 0.8.0, 0.8.1, 0.8.2,0.8.3) to the ones which are compatible to the next versions of AMALTHEA meta model.
+*Model Migration functionality* is part of this distribution, using this feature it is possible to convert models from previous releases (e.g. itea.1.0.3, itea.1.1.0, itea.1.1.1, 0.7.0, 0.7.1, 0.7.2, 0.8.0, 0.8.1, 0.8.2,0.8.3,0.9.0) to the ones which are compatible to the next versions of AMALTHEA meta model.
 
 _Only forward migration of models is supported by Model Migration functionality of AMALTHEA_