remove incorrect information about the api version

The API version is currently not equal to the gitlab major version number. Gitlab 4.1 
still uses API version 3. Point to the lib/api.rb file instead which contains the
autoritative information.

Added swipe view for image diff

Prepared diff view for multiple view modes

Converted commits.js to coffeescript
image info in separate coffeescript file

Added swipe view mode

Added onion skin viewMode

Updates web hooks to process via queue

Feature: Projects page

Missing environment added to 'Try fixing it' block

fix edit project members access link and page fixes refs #2745

Add assign project to team button on team page

Fix not showing tooltip on network graph

A new queue of "project_web_hook" is used to process web hooks asynchronously, allowing each to succeed/fail (and be retried) independently.

(Basically, project web hooks now process the same as system hooks.)