Does not compile on watchOS

[Léo Natan]

Hello,

Great library!
The project does not compile for watchOS. There are complaints about certain types that did not exist in watchOS 2.0 (the minimum target), and usage of CATransform3D, which isn’t exposed on watchOS.

Thanks

[Mhd Hejazi]

I think it's ok to update the minimum target to watchOS 3.0 and define asCATransform3D for iOS and macOS only. I'll do that.

[Léo Natan]

Thank you!