Add rest_client setting
Update classes names to be more clear of what they are
Hard code default REST driver
Add phpdoc to the RestContext::setRestClient
Change remaining 'client' to 'driver'
Merge pull request #962 from MLoureiro/add_rest_client_setting

Add rest client setting
CS: Removed double space in the function definiton
Merge pull request #967 from crevillo/cs-ContentTypeService

CS: Removed double space in the function definiton
Add Guzzle4 driver
Merge pull request #968 from MLoureiro/add_guzzle4

Add Guzzle4 driver