Retire outdated Migrate Welcome page

The "Migrate" page on the Welcome screen has not been updated since
4.29 and no user complained, so remove it. Porting guides are still
maintained in the platform docs and reachable from the help system.

Fixes #2630

Author: vogella

platform/org.eclipse.platform/images/topiclabel/wn_migrate48.svg

@@ -8,9 +8,6 @@ a#updates:hover img { background-image : url(../../images/topiclabel/wn_updates4
 a#eclipse img { background-image : url(../../images/topiclabel/wn_eclcommunity48.svg); }
 a#eclipse:hover img { background-image : url(../../images/topiclabel/wn_eclcommunity48.svg); }
 
-a#migration img { background-image : url(../../images/topiclabel/wn_migrate48.svg); }
-a#migration:hover img { background-image : url(../../images/topiclabel/wn_migrate48.svg); }
-
 div#rss-news {
 	position: relative;
 	top: -25px;

platform/org.eclipse.platform/intro/css/migrate.css

@@ -21,9 +21,6 @@ whatsnew.updates.hover-icon = images/topiclabel/wn_updates48.svg
 whatsnew.eclipse.link-icon = images/topiclabel/wn_eclcommunity48.svg
 whatsnew.eclipse.hover-icon = images/topiclabel/wn_eclcommunity48.svg
 
-whatsnew.migration.link-icon = images/topiclabel/wn_migrate48.svg
-whatsnew.migration.hover-icon = images/topiclabel/wn_migrate48.svg
-
-whatsnew.page-content.layout.vspacing = 40 
+whatsnew.page-content.layout.vspacing = 40
 
 whatsnew.subtitle-id = news/page-content/page-title

platform/org.eclipse.platform/intro/css/migrate.properties

@@ -22,7 +22,6 @@
          <extension id="org.eclipse.ui.workbench.news" importance="low"/>
          <extension id="org.eclipse.jdt" importance="low"/>
          <extension id="org.eclipse.pde.changes" importance="low"/>
-         <extension id="org.eclipse.ui.workbench.migration" importance="low"/>
       </group>
       <group path="page-content/top-right">
          <extension id="org.eclipse.ui.workbench" importance="low"/>
@@ -55,16 +54,4 @@
          <extension id="org.eclipse.pde" importance="low"/>
       </group>
    </page>
-   <page id="migrate">
-      <group path="page-content/bottom-left" default="true">
-         <extension id="org.eclipse.jdt" importance="low"/>
-      </group>
-      <group path="page-content/bottom-right" default="true">
-      </group>
-      <group path="page-content/top-right">
-      </group>
-      <group path="page-content/top-left">
-         <extension id="org.eclipse.platform" importance="low"/>
-      </group>
-   </page>
 </extensions>

platform/org.eclipse.platform/intro/css/whatsnew.css

@@ -87,12 +87,6 @@
       <configExtension
             configId="org.eclipse.ui.intro.universalConfig"
             content="$nl$/intro/whatsnewExtensionContent2.xml"/>
-      <configExtension
-            configId="org.eclipse.ui.intro.universalConfig"
-            content="$nl$/intro/whatsnewExtensionContent3.xml"/>
-      <configExtension
-            configId="org.eclipse.ui.intro.universalConfig"
-            content="$nl$/intro/migrateExtensionContent.xml"/>
    </extension>
 
 

platform/org.eclipse.platform/intro/css/whatsnew.properties

@@ -25,7 +25,7 @@ org.eclipse.ui/SHOW_PROGRESS_ON_STARTUP=true
 org.eclipse.ui.intro/INTRO_THEME = org.eclipse.ui.intro.universal.solstice
 
 # Root page links to show in the Universal Welcome
-org.eclipse.ui.intro.universal/INTRO_ROOT_PAGES = overview,tutorials,samples,whatsnew,migrate
+org.eclipse.ui.intro.universal/INTRO_ROOT_PAGES = overview,tutorials,samples,whatsnew
 
 # Initial page layout of the Universal Welcome
 org.eclipse.ui.intro.universal/INTRO_DATA = product:introData.xml