Attach pinchStart event, fix scaleStart reset value to null

framer/LayerPinchable.coffee

@@ -5,8 +5,8 @@ Utils = require "./Utils"
{Gestures} = require "./Gestures"

Events.PinchStart = "pinchstart"
Events.PinchEnd = "pinchend"
Events.Pinch = "pinch"
Events.PinchEnd = "pinchend"
Events.RotateStart = "rotatestart"
Events.Rotate = "rotate"
Events.RotateEnd = "rotateend"
@@ -38,7 +38,7 @@ class exports.LayerPinchable extends BaseClass
		@_attach()

	_attach: ->
		@layer.on(Gestures.PinchStart, @_pinch)
		@layer.on(Gestures.PinchStart, @_pinchStart)
		@layer.on(Gestures.Pinch, @_pinch)
		@layer.on(Gestures.PinchEnd, @_pinchEnd)

@@ -101,8 +101,8 @@ class exports.LayerPinchable extends BaseClass
		super eventName, event, @

	onPinchStart: (cb) -> @on(Events.PinchStart, cb)
	onPinchEnd: (cb) -> @on(Events.PinchEnd, cb)
	onPinch: (cb) -> @on(Events.Pinch, cb)
	onPinchEnd: (cb) -> @on(Events.PinchEnd, cb)
	onRotateStart: (cb) -> @on(Events.RotateStart, cb)
	onRotate: (cb) -> @on(Events.Rotate, cb)
	onRotateEnd: (cb) -> @on(Events.RotateEnd, cb)