ovr_User_GetAccessToken Function
Return an access token string for this user, suitable for making REST calls against graph.oculus.com.
A message with type ovrMessage_User_GetAccessToken will be generated in response.
If no error occurred, the message will contain a payload of type const char *. Extract the payload from the message handle with
ovr_Message_GetString().
ovrRequest ovr_User_GetAccessToken()