Bug 547080: Show internal links for reqif nested requirements

For reqif requirements, if nested requirements are selected,
internal links are not shown since the current implementation
only checks for children of the specification document.
This has now been changed by getting all the content in the
specification and not only the first hierachy of requirements.
diff --git a/bundles/org.eclipse.capra.handler.reqIf/src/org/eclipse/capra/handler/reqif/ReqIfHandler.java b/bundles/org.eclipse.capra.handler.reqIf/src/org/eclipse/capra/handler/reqif/ReqIfHandler.java
index ae82c98..5de66aa 100644
--- a/bundles/org.eclipse.capra.handler.reqIf/src/org/eclipse/capra/handler/reqif/ReqIfHandler.java
+++ b/bundles/org.eclipse.capra.handler.reqIf/src/org/eclipse/capra/handler/reqif/ReqIfHandler.java
@@ -20,6 +20,7 @@
 
 import org.eclipse.capra.core.adapters.Connection;
 import org.eclipse.capra.core.handlers.AbstractArtifactHandler;
+import org.eclipse.capra.core.helpers.EMFHelper;
 import org.eclipse.capra.handler.reqif.preferences.ReqifPreferences;
 import org.eclipse.core.resources.IResourceDelta;
 import org.eclipse.core.runtime.preferences.IEclipsePreferences;
@@ -92,10 +93,13 @@
 			for(SpecRelation r: relevantRelations) {
 				List<EObject> targets = new ArrayList<>();
 				for (Specification specification : specifications) {
-					for (SpecHierarchy s : specification.getChildren()) {
-						if ((s.getObject().getIdentifier().equals(r.getTarget().getIdentifier()))
-								|| s.getObject().getIdentifier().equals(r.getSource().getIdentifier())) {
-						targets.add(s);
+					for (EObject object : EMFHelper.linearize(specification)) {
+						if (object instanceof SpecHierarchy) {
+							SpecHierarchy spechierachy = (SpecHierarchy) object;
+							if ((spechierachy.getObject().getIdentifier().equals(r.getTarget().getIdentifier()))
+									|| spechierachy.getObject().getIdentifier().equals(r.getSource().getIdentifier())) {
+								targets.add(spechierachy);
+							}
 					}
 				}
 				connections.add(new Connection(investigatedElement, targets, r));