Refactoring

* Split ClientHttp into ClientHttp and ClientBase
* Updated gemspec
* Moved VERSION into Occi::Api
* Updated spec_helper
* Minor fixes in ClientHttp methods to make it
  stable
WIP, modular authentication

* Basic refactoring
* Not tested, probably not working yet
Fixed options
Fixed fallbacks in HTTP authN
Fixed fallbacks in HTTP authN, new approach
Fixed HTTP authN fallback after 401
Fixed case statement in HTTP client authN
Added the concept of 'original authN' in fallbacks
Updated VOMS authN

* --proxy-ca option is no longer needed
* updated reading of multiple certs from a single file
Fixed response parsing after HTTP POST
Fixed Travis-CI (build deps)
Updated unit tests refactored deploy
Fixed RSpec tests; now jRuby friendly
Merge pull request #2 from arax/refactoring

Refactoring; updated authN; new VOMS handling