Backout revert of synchronous clone branch, Fix skybox component to use images instead of textures
[RELEASE] v0.154.6
[VERSION] v0.155.0-dev
Use the current Gamepad API

`webkitGetGamepads` is deprecated in recent browser versions. Provide use of the current API if available.
Merge pull request #35 from playcanvas/feature/synchronous-clone-fix

Synchronous clone
[RELEASE] v0.155.0
[VERSION] v0.156.0-dev
[FIX] pc.Quat#slerp now handles identical input quaterions correctly
Assets no longer have resource ids, Fixed examples for the new asset format
Added CONTRIB file

Fixed some spelling.
Update CONTRIB file with CLA details and tips
Merge pull request #38 from Systemcluster/patch-1

Use the current Gamepad API
[FIX] audiosources with 'activate' false no longer play on startup
[RELEASE] v0.155.1
[VERSION] v0.156.0-dev
Merge pull request #40 from playcanvas/feature/asset-migration

Assets no longer have resource ids, Fixed examples for the new asset format
Use a TextureRequest for skybox textures instead of ImageRequests so that they can be cached correctly and used by other assets like materials without issues
New particle system.
Particle system component, bugfixes
Particle system: added schema, moved emitter creation to onEnable, fixed some actual emission bugs, assets can be used as textures now