Move hide property from indicator classes to abjad.Wrapper #1531
Description
Remove "hide" from __eq__() calculations:
- abjad.Clef
- abjad.Dynamic
- abjad.MetronomeMark
- abjad.MetricModulation
- abjad.TimeSignature
Add "hide" to abjad.Wrapper:
- add abjad.Wrapper.hide
- remove abjad.Clef.hide
- remove abjad.Dynamic.hide
- remove abjad.MetronomeMark.hide
- remove abjad.MetricModulation.hide
- remove abjad.TimeSignature.hide