Opacity adjustments for image diffs

Tom

2014-11-12 3e1336cc6d32511daf2acab9c45a517cd3b10058

 src/test/java/com/gitblit/tests/mock/MemorySettings.java

@@ -48,6 +48,11 @@
   }

   @Override
   public boolean saveSettings() {
      return false;
   }

   @Override
   public boolean saveSettings(Map<String, String> updatedSettings) {
      return false;
   }