v5.0.0

• add parsing for all gamemodes, not just osu!std
  • each gamemodes returns their own ReplayEvent subclasses with specific attributes. See the readme for documentation on each mode's ReplayEvent subclass
• rename ReplayEvent.time_since_previous_action to ReplayEvent.time_delta
• rename ReplayEvent.keys_pressed to ReplayEvent.keys
• change ReplayEvent.keys_pressed (now ReplayEvent.keys) to a new Key enum instead of a raw int