(more) AR features

[dtugend]

• [x] shared targets + interprocess communication
• [x] commands support
• [x] mirv_calcs support
• [x] camera override
• [x] headless mode, so that the AfxHookUnity.dll can be used without Unity / rendering.
• [x] support different render passes so that translucent objects etc can be handled better (v7 afx-cefhud-interop)
• [ ] depth buffer write so that translucent objects etc can be handled better