use Snap / Snap (Pixels) now save to scene file

Previously, only Use Pixel Snap would save to the scene.
Tested and working for me, on Linux.
#298 imp
Merge pull request #330 from jonyrock/complex_undo

#298 imp - thanks!!! - hope you tested this well :)
Merge pull request #318 from adolson/scene-snap-settings-save

2D scene snap settings save
-Added OpenSSL and HTTPS support
-Built-in version of the library for Windows, Android and iOS (other OSs use system one)
-Small fixes all around