Warn when attempting to set an invalid property using set_attributes.
Revamped logger to be very verbose on :verbose, added whitelist for screen instantiation
Use debug mode, not warn
Fix regression - modal= should indeed be applied by set_attributes
Merge branch 'master' into feature/warn-on-invalid-property
Extensive work on tests
Travis fix
Merge pull request #546 from clearsightstudio/feature/warn-on-invalid-property

Warn on invalid properties when using `set_attributes` (:warn or higher)