* Added several unit tests
* Added documentation for new syspurpose option and suboptions
* Simplified specification of module arguments
* Added new changelog file with fragments
* Fixed the redhat_subscription module:
- Option 'pool_ids' works in Python3 now
- It tries to attach only pools IDs that are available
- Optimization of code: do not call list --available, when
no pool is requested
- Simplified configure() method
- Small changes to generate same commands on Python2 and Python3.
Order of arguments/options and pool IDs have to be same to
be able to run unit test using Python2 and Python3.
- Added fragments file for redhat_subscribtion module
