Fix for #48.

Rework of how services are sorted based on dependencies using a topological sort.
Includes error handling to detect circular/self imports (should raise a DependecyError).
Added in logging to the CLI to log out any DependencyErrors.
Removed the compact module as it is no longer used.
Merge pull request #52 from cameronmaske/fix-sort-service-dicts

Fix for #48