Update release notes

Change-Id: I4426743500a8feb27eda0f5d22f1601fcad7f2ab

WebContent/release-notes.html

             enhancements. Below is a list of the most notable changes:</p>
 
         <ul>
-            <li>Column reordering using drag and drop in Grid</li>
-            <li>Column hiding in Grid</li>
-            <li>Row details support in Grid</li>
-            <li>JSR 356 WebSocket support has been refactored to improve compatibility with Wildfly and WebLogic</li> 
+            <li>Completely new reconnect dialog</li>
+            <li>Grid unbuffered editing</li>
+            <li>Grid keyboard navigation enhancement</li>
         </ul>
 
         <p>
-            For enhancements introduced in Vaadin 7.4, see the <a
-                href="http://vaadin.com/download/release/7.4/7.4.0/release-notes.html">Release
-                Notes for Vaadin 7.4.0</a>.
+            For enhancements introduced in Vaadin 7.5, see the <a
+                href="http://vaadin.com/download/release/7.5/7.5.0/release-notes.html">Release
+                Notes for Vaadin 7.5.0</a>.
         </p>
 
         <h3 id="incompatible">Incompatible or Behavior-altering Changes in @version-minor@</h3>
                 it must list all close shortcuts, including ESCAPE, separated by whitespace. Existing, unchanged code should
                 behave as before. See ticket <a href="https://dev.vaadin.com/ticket/17383">#17383</a> for more information 
                 on the reasoning behind the change.</li>
-            <li>The push path has been changed from /PUSH/ to /PUSH to be compatible with JSR 356.</li>
-            <li>Widgetset files and other pre-compressed resources are sent as gzip to compatible browsers.
-                This may interfere with custom response compression solutions that do not respect the Content-Encoding response header.</li>
-            <li>Unused methods related to the "out of sync" message have been removed from SystemMessages class.</li>
-            <li>All notifications use the WAI-ARIA alert role to be compatible with Jaws</li>
             <li>Grid SelectionModels are now Extensions. This update removes all selection related variables and API from 
             GridConnector, GridState, GridServerRpc and GridClientRpc</li>
         </ul>