Added
* Extend ams library to support offset manipulation
* Introduce AmsHttpRequests class
* Common methods for PUT, GET, POST requests
* Tests for backend error messages that could be plaintext or JSON encoded
* Failed TopicPublish and CreateSubscription tests
* Separated error mocks
* Extend ams library to support offset manipulation
* Grab methods from class namespace
* Tests for bogus offset specified
* Added missed 'all' value for offset argument
* Handle 404 for topic and subscription calls
* Handle JSON error message propagated through AMS
Fixed
* set for error codes and pass request args for iters
* Status msg attach to AmsServiceException if exist
* Topic ALREADY_EXIST error test
* Fix returnImmediately parameter in sub pull request
* Remove not raised TypeError exception handles
* Refactored error handling with error routes
* Offsets method with combined logic of get and move offsets