Fix function name(use 'hunk' instead of 'diff')

And those aliases for backward compatibility
Add docstring to interactive functions
Update for git-gutter:next-hunk and previous-hunk
Fix git-gutter:toggle-problem(#13)
[EXPERIMENTAL] Implement git-gutter:revert-hunk
Add tests of utility functions.
Update document and formatted
Add sample setting of git-gutter:revert-hunk
Fix git-gutter:toggle problem(#15)
Fix Sublime Text2 => Sublime Text
Update tests
[EXPERIMENTAL] support tramp
Bump up version and update Changes