remove the unhelpful stack trace setup, using gdb on server for now
Merge pull request #258 from birarda/stacktraces

remove the current un-helpful stacktrace setup
Merge pull request #259 from birarda/mixer-crash

fix the audio-mixer crash for uninitialized _shouldLoopbackForAgent variable
Merge pull request #260 from birarda/mixer-crash

more fixes for audio mixer crashing:
perform send of audio buffer on main thread
Merge remote-tracking branch 'upstream/master' into mixer-crash
resolve conflicts on merge with upstream master
make the audio mixer socket non-blocking so it doesn't halt waiting for data