Version 0.4.0

Features

• Breaking: removes is_protocol boolean argument from .instance,
  now use protocol=YourProtocol instead
• Adds support for concrete generic types like List[str] and Set[int] #24
• Adds support for types that have __instancecheck__ defined
  via delegate argument #248
• Adds support for multiple type arguments in Supports type #244

Bugfixes

• Fixes that types referenced in multiple typeclasses
  were not handling Supports properly #249
• Fixes typing bug with ABC and mutable typeclass signature #259
• Fixes that mypy plugin was failing
  on calling a typeclass without arguments #270