head penumbra filter tuning with Freddy / filter defaults to on
Merge branch 'master' of https://github.com/highfidelity/hifi into audio-noise

Conflicts:
	assignment-client/src/audio/AudioMixer.cpp
Merge branch 'master' of https://github.com/highfidelity/hifi into audio-noise
Merge branch 'master' of https://github.com/highfidelity/hifi into audio-noise
Merge branch 'master' of https://github.com/highfidelity/hifi into audio-noise
clamp to 0.0f when within EPSILON neighborhood of 0.0f
default sine gain set to -6db
disable positional filter by default
Merge pull request #3457 from chansensturm/audio-noise

Set default for head-penumbra filter to off