Use static for cache dir and cache extension to eliminate mutex lock overhead to generate cache file path

following promotion of DRTVWR-519

Port the old texture picker.

See merge request alchemy/alchemy-next!14

This adds Transparent texture button, and UUID input box.

following promotion of DRTVWR-517

Expand Rez Under Land Group to general item rezz

See merge request alchemy/alchemy-next!13

Add option to control hover text fade distance and range.

See merge request alchemy/alchemy-next!12

Why does LL have such a weird standard?

No UI yet.