added SKNode plugin

Conflicts:
	Test/SpriteKitReader-Experimental/SpriteKitReader-Experimental/SKReaderTestData.spritebuilder/Source/Resources/Published-Android/MainScene.ccbi
	Test/SpriteKitReader-Experimental/SpriteKitReader-Experimental/SKReaderTestData.spritebuilder/Source/Resources/Published-iOS/MainScene.ccbi
	Test/SpriteKitReader-Experimental/SpriteKitReader-Experimental/SKReaderTestData.spritebuilder/SpriteBuilder Resources/MainScene.ccb
	Test/SpriteKitReader-Experimental/SpriteKitReader-Experimental/SKReaderTestData.spritebuilder/SpriteBuilder Resources/MainScene.ccb.ppng