Fixes findbugs warning - dereferencing null in exception case

Simon Harrer

2013-07-18 fbe265fa787e4be9cb63c6bae2ef30b9400d9afc

 src/main/java/com/gitblit/wicket/pages/ComparePage.java

@@ -103,6 +103,9 @@
            toCommit = getCommit(r, toCommitId.getObject());
         }

         // prepare submodules
         getSubmodules(toCommit);
			
         final String startId = fromCommit.getId().getName();
         final String endId = toCommit.getId().getName();