SL-14098, enable occlusion culling during reflection pass

Approved-by: Michael Pohoreski

SL-16127 More tweaks

Approved-by: Euclid Linden
Approved-by: Dave Parks

SL-16148 SL-16244 SL-16270 SL-16253 Remove most BlockTimers, remove LLMemTracked, introduce alignas, hook most/all reamining allocs, disable synchronous occlusion, and convert frequently accessed LLSingletons to LLSimpleton

SL-16127: Make another pass removing redundant LLSD op [] calls, unused vars, and use atmospheric already calculated

SL-16127

Approved-by: Euclid Linden
Approved-by: Dave Parks

SL-16127: Make another pass removing redundant LLSD op [] calls, unused vars, and use atmospheric already calculated

SL-16193 Fix for mesh selection outline not rendering correctly (and broken physics shapes display).

SL-15999 support --noninteractive option for viewer

Approved-by: Dave Parks
Approved-by: Michael Pohoreski

SL-16222 Don't use bindFast for legacy bump maps (weird loading path sometimes has stale texture state).

SL-16127: Fix bug in int() not calling getDistanceMultiplier(), calc() not calling getTotalDensity()