start of the ranges gets clamped with a wrong value. In case of a texture with
601 byte long texture the viewer request range 0-599 first, then 600- in which case
both start and end should be 600.
End can also be 0, valid request for the firt byte of the file is 0-0.
Thanks to Thickbrick for explaining how HTTP range header works.
* Adds GetTextureModule that implements the "GetTexture" capability, aka HTTP texture fetching. This is a significantly optimized path that does not require any server-side JPEG2000 decoding, texture priority queue, or UDP file transfer
* Sanity check for null reference in LLClientView.RefreshGroupMembership()