Allow to use namespace api.

`$client->api('namespaces')->all();`
Merge pull request #37 from gonimar/patch-1

Allow to use namespace api.
Add merge method to MR API
Use LSB on class instanciation to ease extending them
Handle MR description
Added ability to specify activation types when creating or updating project hooks
Merge pull request #41 from tyler-sommer/feature/hooks-update

Specify project hook types
Merge pull request #40 from jubianchi/mr-description

Handle MR description
Merge pull request #39 from jubianchi/use-static

Use LSB on class instanciation to ease extending them
Merge pull request #38 from jubianchi/mr-accept

Add merge method to MR API
Add a method to retrieve an issue's comments
Add a method to retrieve a mr's comments
Merge pull request #42 from jubianchi/issue-show-comments

Issues/MRs show comments
Fix merge method : use static
Add missing method to MR API
CS fix
Link snippets API (Fix #43)
Json decode only responses with json content type

When I wanted to get code of JSON file (that exists in repository) using blob API method, I got parsed JSON, but I wanted plain text...
Url: projects/<project id>/repository/commits/<sha>/blob?filepath=<some json file>
'$this' is better than 'parent'
Merge pull request #44 from schneidermichal/master

Json decode only responses with json content type