Enables WebGL in all web views.

Seatbelt causes kernel to block Safari and Web.app clips from loading OpenGL :( To fix kill off MobileSafari's code signature:

1. Backup /Applications/MobileSafari.app/MobileSafari
2. Copy MobileSafari to a mac that has codesign
3. Run codesign --remove-signature /path/to/MobileSafari.app/MobileSafari
4. Transfer it back to the device and overwrite the existing MobileSafari
5. Apply to /Applications/Web.app/Web
6. Install WebGLEnabler