Command split: Create the Commands::Command class

This will be the superclass of all classes implementing commands.
Command split: Implement the "clone" command in a separate class
Command split: Implement the "genpatch" command in a separate class
Command split: Implement the "patch" command in a separate class
Command split: Implement the "reset" command in a separate class
Command split: Implement the "restructure" command in a separate class
Command split: Implement the "ybc" command in a separate class
Command split: Implement the "ruby" command in a separate class
Command split: Implement the "makefile" command in a separate class
Command split: Implement the "package" command in a separate class
Command split: Implement the "convert" command in a separate class
Command split: Cleanup the YastModule class
Merge pull request #233 from yast/create-command-classes

[Review] Request from '' @ 'yast/ycp-killer/create-command-classes'