following promotion of DRTVWR-577

BUG-233797/233798 - fix blackout when u/w fog_density < 0 

Newer C++ compilers have different semantics around LLSDArray's special copy
constructor, which was essential to proper LLSD nesting. In short, we can no
longer trust LLSDArray to behave correctly. Now that we have variadic
functions, get rid of LLSDArray and replace every reference with llsd::array().

It seems newer compilers have a different interpretation of exactly when to
engage LLSDArray's copy constructor. In particular, this assignment:

some_LLSD_map[key] = LLSDArray(...)(...)...;

used to convert the LLSDArray object directly to LLSD; now it first calls the
custom copy constructor, which embeds the intended array within an outer array
before assigning it into the containing map.

The newer llsd::array() function avoids that problem because what it returns
is already an LLSD object.

Taking inventory of LLSDArray assignments of that form turned up a number of
workarounds like LLSD(LLSDArray(...)). Replacing those with llsd::array() is
both simpler and more readable.

Tip of the hat to Chorazinallen for surfacing this issue!

(cherry picked from commit bb718155)

following promotion of DRTVWR-539

# Conflicts:
#	indra/integration_tests/llui_libtest/CMakeLists.txt
#	indra/newview/llfloateravatarrendersettings.cpp

This reverts part of commit 0c2b00ef.

# Conflicts:
#	indra/cmake/CMakeLists.txt
#	indra/newview/skins/default/xui/es/floater_tools.xml

following promotion of DRTVWR-573

to make it accessible after updating the viewer

Should fix "Radio/Stream hiccups at a regular rate during playback"

# Conflicts:
#	indra/cmake/Copy3rdPartyLibs.cmake
#	indra/cmake/FindOpenJPEG.cmake
#	indra/cmake/OpenJPEG.cmake
#	indra/integration_tests/llui_libtest/CMakeLists.txt
#	indra/newview/CMakeLists.txt

The viewer currently presents a startling "Grid emergency" warning if an
unrecognized error is returned from login. Let's tone this down a bit
and present the error as it is: an unrecognized login failure rather
than SLearth exploding.

Disable NvAPI by default

Win7 is no longer supported and is below minimal requirements

added missing app setting