LLWord should persist till the end due to wide usage.

Pausing clouds should not pause water

# Conflicts:
#	indra/llcommon/llsdutil.cpp
#	indra/newview/VIEWER_VERSION.txt
#	indra/newview/lldrawpoolalpha.cpp
#	indra/newview/lldrawpoolwater.cpp

following promotion of DRTVWR-540

SL-17194 Impostor quality pass 2 (and fix for fully transparent rigged attachments rendering to depth buffer)

This reverts commit b45c0e3e.

SL-17074 Redo ALT-F4 handling fix

Merged previewAvatar and generateImpostor into a single function since they are nearly identical

SL-17000 improve error message for physics mesh import

SL-17077 Ensure profiling is disabled if gpu_benchmark fails.  Log the source of the real crash for when the viewer inevitably crashes later.

SL-16993

Approved-by: Euclid Linden

SL-17028 Fix for inconsistent ordering of transparent rigged meshes and removal of glow-only rigged meshes from depth buffer.

SL-17074 Fix Alt-F4 handling bug