Added tests and support for RPM.

Mirror the functionality of yum list installed with better output format.
Add test and support for using yum's createrepo tool.
Add test and support for using yum's repotrack tool.
Extend Yum.update to allow an optional list of packages as arguments.
Adding Hash store_path
Add gem to parse files with ini type contents
Add parsing of Yum repo files with tests and sample data.
Add common write command for use in writing config files.
Add a common method to sanitize user input for the command line.
Add more options to Subscription Manager registration
Extending Yum to get the latest available version for package(s)