= Several Major Internal Changes
  - Several parts of GitGutter have been rewritten to make it perform
    better, and more able to make changes going forward including
    the following specific improvements:

* Diff Popup
  - Add a mode to toggle the highlight mode of the diff popup between
    "syntax highlighting" and "differences highlighting".

* Async Invocations
  - GitGutter now runs in a separate thread using promises to update
    the gutter when finished.
  - non_blocking setting is gone, it is always non blocking now.

* Temporary Files
 - Make sure temporary files are deleted after view is closed.
