v0.5.0

Major changes

• Introduce a custom scale gesture detector implementation. The library doesn't rely on the compat gesture detector anymore. This is a breaking changing because the underlying scale gesture detector reference has been removed. #73

Minor features and bug fixes

• Calculate focal point for every motion event, not only MOVE. Fixes an issue where detectors that do not rely on movement would return cached, historic focal points. #77
• Adjust scale gesture's required pointer count based on type. Fixes an issue where quick-scale was not properly interrupted. #74
• Guard against move events coming from different view trees. Might prevent rare crashes that are out of control of the gestures library. #71
• Expose scale span getters. #75