Merge pull request #3156 from m4tthumphrey/api-system-hooks

Added methods to manage system hooks from API
Merge pull request #3149 from m4tthumphrey/api-deploy-keys

Added methods to manage project deploy keys via API
Use secure protocol
Merge pull request #3158 from dosire/master

Use secure protocol
update Gemfile.lock with https rubygems
add system hooks api docs to help content
fix js syntax error
show highlighted code correctly inside issue body
Return project description back
Allow connection to Redis via unix socket

Allow connection to Redis via unix socket, using
unix:/var/run/redis/redis.sock for example.

Default behaviour does not change, except that the full Redis URL must
be configured, with redis:// for tcp or unix: for unix socket.
API: documentation contains infos to status codes in README file.

All the info to return codes from the API functions are available in the `README.md` file as suggested.
Refactor README to split production/development environments
Refactor: replace "render :json = graph.to_json" to view template(show.json.erb).

Because model shouldn't know about view logic.
Refactor: grouping parent and their space by including array.
Merge pull request #3161 from cabello/patch-1

Refactor README to split production/development environments
Refactor: rename module and class names.

* Module: Graph -> Network
* Class: JsonBuilder -> Graph
Merge pull request #3159 from peikk0/allow-redis-via-socket

Allow connection to Redis via unix socket
Merge pull request #3146 from amacarthur/AdminAPIs

Additional Admin APIs
show project description on public area
Refactor: clean up models.

* Network::Commit
** Removing unnecessary accessors.
** Removing add_refs methods.
* Network::Graph
** Removing unnecessary accessors.
** The 3 times loop of commits don't need.