Bug 568135 - Add doc for "Enable auto scroll lock" pref

Add a description of the "Enable auto scroll lock" preference option to
the Console Preferences reference page

Change-Id: I3065365190906874b080a3eec12186345e32e146
Signed-off-by: Christian Gabrisch <eclipse@cgabrisch.de>

bundles/org.eclipse.jdt.doc.user/reference/preferences/run-debug/ref-console.htm

diff --git a/bundles/org.eclipse.jdt.doc.user/reference/preferences/run-debug/ref-console.htm b/bundles/org.eclipse.jdt.doc.user/reference/preferences/run-debug/ref-console.htm
index 57e354a..7835044 100644
--- a/bundles/org.eclipse.jdt.doc.user/reference/preferences/run-debug/ref-console.htm
+++ b/bundles/org.eclipse.jdt.doc.user/reference/preferences/run-debug/ref-console.htm
@@ -109,6 +109,22 @@
         </tr>
         <tr>
           <td colspan="1" valign="top" align="left">
+            Enable auto scroll lock
+          </td>
+          <td colspan="1" valign="top" align="left">
+            This preference controls whether the console view enables and
+            disables scroll locking automatically. When on, scroll locking is
+            enabled as soon as the user scrolls up the console output. It will
+            be disabled once the user scrolls to the end of console output.
+            Scroll locking prevents the console view from immediately returning
+            to the end of console output in response to changes.
+          </td>
+          <td colspan="1" valign="top" align="left">
+            On
+          </td>
+        </tr>
+        <tr>
+          <td colspan="1" valign="top" align="left">
             Enable word wrap
           </td>
           <td colspan="1" valign="top" align="left">