FEATURE (editor): add vim mode

- add vim mode to editor (enable from settings)

Closes #95
FIX (single gist): wrong direct link for uppercase characters in filename or extension

- fix wrong direct link for uppercase characters in filename or extension

Closes #93
FIX (editor paste): paste now updates correctly in the angular file model.

Fixes #94
FIX (edit mode): Edit mode is now canceled upon route change

 in order to prevent getting stuck in edit mode causing being unable to access most of the app features edit mode gets set to false on route changes.

Fixes #96
FIX (Open file in browser): Open file in browser is now opening correctly with filenames that contain spaces.

Fixes #97
FIX (Revision view): Fix revision broken due to a syntax error
FIX (Github file links): Add new filter to handle all github naming concentions on urls (spaces, dots and case).
RELEASE: 0.2.6b
TOOLS (bower): Add bower dependency management. Update socket.io to version 1.0.6

Fixes #90
FIX (global): update 1.2 branch to new changes
IMPROVE (angular): Update angular to 1.2

Fixes #89