Merge pull request #1140 from ZappoMan/bugfixes

flip mirror tools
Rear view zoom level

new zoom icons
save and restore state from settings
display zoomed out rear view when selected
Merge branch 'master' of https://github.com/worklist/hifi into 19447

Conflicts:
	interface/src/ui/RearMirrorTools.cpp
fix packetData memory leak in AvatarMixer
add debug to catch AvatarMixer ghosting
remove the ground plane
add debug for sleep amount to AvatarMixer
Merge pull request #1143 from birarda/assignment

add node kill debugging, remove ground plane
made sending environments off by default
Merge pull request #1144 from ZappoMan/stephens_requests

made sending environments off by default
have silent node removal flag reset on join
reference global with colon
Merge pull request #1145 from birarda/assignment

fix silent node removal thread join bug
added --getOctalCode to voxel edit
Merge pull request #1146 from ZappoMan/stephens_requests

added --getOctalCode to voxel edit so you can easily make jurisdictions from arbitrary voxels
Normal map support almost there.
Sign change.  Forgot we flip the texture coordinates.
Merge branch 'master' of https://github.com/worklist/hifi into ick
Merge pull request #1141 from stojce/19447

Code Review for Job #19447
Looks like setCentralWidget is ending up calling the init functions in newer
versions of Qt.  Initialize the network access manager before that happens.