v2.0.0

[v2.0.0] - 2022-04-26

Added

• Add raise_on_giveup keyword arg for decorators
• Add backoff.runtime wait generator for dynamically setting wait times based
  on target function return value or exception details

Changed

• Improve type hints for on_success, on_backoff, on_giveup handlers
• Use decorator-specific detail and handler type hints
• Optionally use typing_extensions for python 3.7 type hinting
• Drop python 3.6 support
• Add python 3.10 support