Kills local voxels if voxel server is removed from NodeList
- added notification hooks to NodeList
- implemented hooks in VoxelSystem to kill local voxels when
  voxel server is killed
Merge branch 'master' of https://github.com/worklist/hifi into multiple_voxel_servers
fix compiler warning
small tweak
adding jurisdiction to scene stats to implement add/drop effect, added command line to voxel server to not send environments
correctly handle freeing of memory for _jurisdictionRoot in VoxelSceneStats
Merge branch 'master' of https://github.com/worklist/hifi into multiple_voxel_servers

Conflicts:
	libraries/avatars/src/HandData.h
added notifications with jurisdiction details for when voxel servers come and go
added visulization for voxel add/kill
Tuned gyro look, added better preferences
Merge branch 'master' of https://github.com/worklist/hifi into touchLook
fix build buster
Merge branch 'master' of https://github.com/worklist/hifi into multiple_voxel_servers

Conflicts:
	interface/src/Application.cpp
Merge pull request #794 from ZappoMan/multiple_voxel_servers

Visualization for Voxel Server Add/Kill
fixed packets per second command line with new frame rate
add fade effect to voxel add and delete, fix crash with audio injector
Merge pull request #796 from PhilipRosedale/touchLook

Tune gyros, always fly in direction of sight, head always moves with gyros, adjustable view sensitivity
Merge pull request #797 from machinelevel/dev4

Rave demo changes per Ryan's request: Darken the world when you're in ra...
Merge pull request #798 from ZappoMan/multiple_voxel_servers

fixed packets per second command line with new frame rate
Merge pull request #799 from ZappoMan/fun_fade

add fade effect to voxel add and delete, fix crash with audio injector