v1.6.4 patch

Added new help tabs on HELP frame: Ambisonics and Presets.
Fix the missing video mapping and projection setting when saving a video preset.
Start the Microsoft's on screen keyboard in minimized state to taskbar when a user want to use only the mouse and keyboard by deactivating the VR Controllers (VR Keyboard) in ‘desktop mirror’ mode (e.g. play a video game).