Merge pull request #3 from desmondmorris/master

Removes request object dependency from MobileCommons class constructor
Merge pull request #4 from desmondmorris/master

Fixes travis test runner
Added method to subscribe/unsubscribe numbers in Mobile Commons
- separate request method used because these calls use the web form API, not the normal rest API
- company_key can be set and used for the opt-out
Merge pull request #5 from jonuy/master

Added method to subscribe/unsubscribe numbers in Mobile Commons