SL-321: remove redundant const declaration of MD5HEX_STR_SIZE in llversioninfo, remove extraneous python variable assignment in CMakeLists, run tests with INFO

SL-321: fix merge removal of mIsFirstRun definition, remove pyinstaller from viewer cmake, now in VMP package cmake

This is already done for TeamCity builds in build.sh, but since we don't yet
have 64-bit Xcode 8 Mac Havok working in the viewer, make plain developer
autobuild builds work also.

converting to logging so that stdout from its command can be captured
cleanly
Make the default be to not print anything

At some point the INTEGRATION_TEST_llurlentry build changed so that the
library(ies) we attempted to stub out got linked in anyway, so that instead of
simplifying the test, the stubs broke it with "duplicate symbol" errors.
Commenting out the stubs permits the test program to succeed.

Instead, since gSavedSettings is an LLControlGroup and LLControlGroup derives
from LLInstanceTracker, just look up the LLControlGroup with canonical name.

As of now, this fork requires Xcode 8, which introduces support for the -quiet
switch.

First batch of changes to add LibVLC media plugin to macOS viewer. Plugin fails to start because of an as-yet undiagnosed issue with VLC plugin files related to their extyended attributes

and re-enable breakpad symbol generation.

The CMake directive that passes VIEWER_CHANNEL to the C++ compiler as
LL_VIEWER_CHANNEL was enclosing the VIEWER_CHANNEL value in double quotes. At
this point in history, those double quotes literally become part of the
LL_VIEWER_CHANNEL value, causing the viewer to construct a bad Viewer Version
Manager query containing those double quotes. Removing them fixes the query.