Update Facepunch.XR and defs to 24b8e70e5c89d04b3f42d8b022bf97e05b82349f, adds check for headset/runtime availablity
VR initialization changes - always load VR extensions if there's a runtime and headset available, so we can init mid-session
Editor: Make ToggleSwitch look nicer
Add toggle switch in editor for VR
https://files.facepunch.com/alexguthrie/1b0711b1/sbox-dev_k3x5LXNKca.png