Copy3rdPartyLibs needed to copy the now-corrected fmodexL libraries
and it had a bad library reference on Linux for release.  In
llaudio land, the audio engine interfaces, even the fmodex
specializations, seem to want to be external-structure free
so use a forward declaration and pointer to FMOD_DSP_DESCRIPTION
and deal with it in the ctor/dtor.

- Removed logging for MAINT-3555
- Added NULL guard to fix MAINT-3703 (hopefully)

MAINT-3016 FIX Viewer freeze... by reverting fix for MAINT-2849 (certain streams do not play) - freeze more important than no play

Quieten down writing to fmod.log - only write errors - speculate this is related to audio stutter/frame stalls

OPEN-173 FIX FMODEx Music stutters once every few seconds (OSS patch via Latif Khalifa & Siana Gearz)

Point autobuild at newer fmodex builds and fix warning being treated as error in llaudioengine_fmodex.cpp

Fleshed out target_link_libraries dependencies between libraries.  Appearance utility now reads avatar_lad.xml during stubbed out params processing.