fpsVR Updated - 1.4 WMR Support

The fpsVR has been updated with the following changes:

• fpsVR now support WMR headsets (within OpenVR API/SteamVR). For more info please read: Q&A
• New feature: "Floor Fix"
  Floor fixes are permanent for Vive/VivePro, but temporal for WMR (SteamVR doesn't pass changes to Mixed Reality Portal).