- Added neobundle#tap(), neobundle#untap(), neobundle#tapped features.
- Improved documentation.
Check for :NeoBundleDepends explicitly

According to the documentation for "exists()" the return value should be
compared to "2" when checking for a command's existence.
Merge pull request #178 from glts/improve-NeoBundleDepends-doc

Check for :NeoBundleDepends explicitly
- Added g:neobundle#types#git#enable_submodule.