added sprite kit template project to /Support

the project (code) is not yet functional, the important part was to have a project that was generated with the builddistro script and spritebuilder could unzip and create the project
fixes for the cocos2d project template in /Support

some txt/changelog files were copied to the bundle (causing warnings in one case)
updated build settings (warnings mostly, reasonably defensive settings)

tried to enable arm64 builds but reverted due to cocos2d causing compile errors with arm64, but left the deployment target as 5.1.1 for now
added menu item to create sprite kit project
added "engine" setting to ProjectSettings to differentiate CC vs SK
updated ProjCreator to create different project based on "engine"
BuildDistribution.sh: added zip & copy of generated sprite kit template project
.gitignore: added SPRITEKITPROJECTNAME