2.5.0 Major Update

Huge update to Lottie!

• Adds a new API for dynamically changing animation properties at run time:
  Docs http://airbnb.io/lottie/ios/dynamic.html
  Tutotial http://airbnb.io/lottie/ios/dynamic_properties.html

• Adds a new api for adding arbitrary subviews and geometry conversions:
  http://airbnb.io/lottie/ios/addsubviews.html

• Adds support for time remapping

• Several Bug fixes

NOTE:
The old api for changing keyframes and adding subviews has been deprecated. Please move to the new system. The methods will be removed in a future version.