First round of settings serialization.  Setup an API to load and save different settings to the avatar data file.
Initial serialized settings:
Gyro look
Mouse look
Transmitter drives
Voxel rendering
Voxel textures
Star rendering
Atmosphere rendering
Avatar rendering
Oculus rift mode
Render stats
Frame stats
Look at vectors
Logging
Frustum debugging
View frustum offset
Camera frustum
Setup various debug options.
Documentation for #19308.
Store settings in an ordered map to allow for runtime getting and setting of settings.  Read the setting file on startup, then write on shut down.
Check how many matches were found for the given data type we're checking for.  1 for bool and float, 3 for vec3.  Return false and assign default values if this isn't true.
add --local option to avatar-mixer
fixed some glitches in avatar render alpha transition between 3p and 1p
Merge pull request #446 from Ventrella/master

fixed some glitches in avatar render alpha transition between 3p and 1p
one line fix for translucent head
Merge remote-tracking branch 'upstream/master' into one-liner
Merge pull request #447 from PhilipRosedale/one-liner

fix for translucent head
add debugging for current mixer crash
more debugging to track down a mixer crash
last pieces of debugging for mixer crash
don't use audio when the bearing sent by the agent is garbage
fix the isnan check for agent bearing
fix to head transparency
Merge remote-tracking branch 'upstream/master'
kill agents who send NaN bearings
remove debugging used to track down mixer crash