Merged in ruslantproductengine/viewer-cougar-4cr-2 (pull request #15)

MAINT-8836 - Objects with Alpha Masking > 0 do not rendering correctly on avatar

Approved-by: Graham Madarasz <graham@lindenlab.com>
Approved-by: Andrey Lihatskiy <andreylproductengine@lindenlab.com>
Approved-by: Simon Linden <simon@lindenlab.com>