Remove deprecated Omnibus.configure method
Omnibus.load_configuration requires a valid filepath
Add a deprecation message for invoking Omnibus.config
Remove uses of Omnibus.config in the code
Document attr_writer for logger
Document Omnibus.ui method
Deprecate Omnibus.project_root in favor of Config.project_root
Reset Omnibus between each test
Stub the correct "Config" object
Fix broken refactor method airty
Update Omnibus.source_root API