Easy fix for Avatar height on OculusGO / GearVR

[treeviewstudios]

Well, many will find this bug that the avatar keeps floating above normal level or below, so what i did was:

1)Override OVRAvatarDriver
2)Go where the HeadPos is set 
3)Add or Substract a number to the headPos variable in CalculateCurrentPose()

code: https://pastebin.com/H31N9zvi

I did this with Photon PUN + Avatar SDK + VRTK.