0.20.0

Changes

• Remove Python 2 compatibility code (#17) @smurfix

Major Changes

• Rename ruamel.yaml to ruyaml (#16) @smurfix

Minor Changes

• Fix and enforce mypy (#24) @ssbarnea
• Enabled generic pre-commit checks (#21) @ssbarnea

Bugfixes

• Fixed linters (#30) @ssbarnea
• Removed old style class definitions (#23) @ssbarnea
• Enable black and isort (#22) @ssbarnea

Deprecations

• Simplified compat module (#19) @ssbarnea