Excalibur v0.12.0

Thanks to @Crizzooo, @htalat, and @vritant24 for their contributions!

Breaking Changes

• CollisionType.Elastic has been removed
• Promises.wrap has been replaced with Promise.resolve

Added

• Added new hsl and hex format options in Color.toString(format) using rgb as the default to maintain backwards compatibility (#852)

Changed

• Animation.loop property now to set to true by default (#583)
• Added backgroundColor to engine options as part of Engine constructor (#846)

Deprecated

• ex.Scene.children is now ex.Scene.actors (#796)