Bump JGit to v4.0.0.201506090130-r

This JGit version includes the bugfix [1] which is an attempt to fix the
"Cannot read project" issue in Gerrit, as discussed in [2] and [3].

This version of JGit also removes the 'release()' method in many
interfaces/classes in favor or the implementing the AutoCloseable
interface. In stable-2.10 we just replace all usages of the release()
method with the close() method. Refactoring the code to make use of the
AutoCloseable in stable-2.10 would be a larger change which wouldn't
justify itself as we don't expect any major development in stable-2.10
and the usage of AutoCloseable in the master branch is already done.

[1] https://git.eclipse.org/r/48288
[2] https://groups.google.com/forum/#!topic/repo-discuss/ZeGWPyyJlrM
[3] https://groups.google.com/forum/#!topic/repo-discuss/CYYoHfDxCfA

Change-Id: Ie540296238e3bbaf453c9e29426825431e15d423
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

gerrit-pgm/src/main/java/com/google/gerrit/pgm/init/AllProjectsConfig.java

@@ -136,15 +136,15 @@ public class AllProjectsConfig extends VersionedMetaData {
           updateRef(repo, ident, newRevision, "commit: " + msg);
           revision = newRevision;
         } finally {
-          rw.release();
+          rw.close();
         }
       } finally {
         if (inserter != null) {
-          inserter.release();
+          inserter.close();
           inserter = null;
         }
         if (reader != null) {
-          reader.release();
+          reader.close();
           reader = null;
         }
       }