Completed worklist job #19486

Job #19486  Don't render the duplicate triangles between adjacent
voxels.

Added checkable item to "developer" menu to activate/deactivate cull
shared faces.

Cull all shared voxel faces regardless of distribution in the octree.
Includes leaf to leaf, leaf to non-leaf, and non-leaf to non-leaf
comparison of contiguous faces.

Added new GL primitive renderer to manage the transfer of cube faces
from the voxel system to GL.

Added some useful classes for queue and lock management.

Modified statistics collection to report number of completely culled
nodes. Extra debugging info also includes the interior occlusions bit
mask of leaf voxels.
Merging upstream
Fixes for style conformance
Fixes for style conformance: tabs to spaces
ADDED the fields in interface-preferences for display name editting
Fixes for style conformance: replace constants with enums
Added new display mode to show culled faces. More statistics.
Added new display mode to show culled faces.
Fixes for style conformance: tabs to spaces
Fixes for style conformance: replace stl containers with Qt
Interface OS X hifi URL scheme
Fixes for style conformance: tabs to spaces
Use vector of primitives instead of associative map
Merge branch '19489-2' into 19489
Custom URL handler
Merge branch 'master' of https://github.com/worklist/hifi into 19494
Always facing camera billboard
TODO: having constant fix size
Constant size in 3D world billboard text
Replaced iterator with const_iterator
Removed duplicate pathway to updateNodeInArrays from showAllSubTreeOperation