Implemented the IssueList class and started working on transition to OOP.
Renamed class IssueList to Tray and moved it to the standalone module.
Added simple setup functionality.
Implemented Issue.create() functionality for issues as XML files.
Implemented show() and edit() functionality for the Issue class.
Minor formatting tweaks.
Included the license file.
Implemented delete() method for the Issue class.
Implemented review() and clear() methods for the Tray class.
0.02 release.