Started on ambient occlusion shader.
Merge branch 'master' of https://github.com/worklist/hifi into ssao
Started on C++ side of SSAO effect.
Merge branch 'master' of https://github.com/worklist/hifi into ssao

Conflicts:
	interface/src/Application.h
Missed a spot in the merge.
Remove the code here; will be replacing it based on glow effect work.
Merge branch 'master' of https://github.com/worklist/hifi into ssao
Beginnings of ambient occlusion.  Looks like an architectural drawing.
Merge branch 'master' of https://github.com/worklist/hifi into ssao
Basic ambient occlusion effect up and running; needs tweaking and
optimization.
Square vector lengths to bunch them up towards the center, add a minimum
length, include the URL of the SSAO tutorial.
Merge branch 'master' of https://github.com/worklist/hifi into ssao

Conflicts:
	interface/src/Application.h
Merge branch 'master' of https://github.com/worklist/hifi into ssao
Merge branch 'master' of https://github.com/worklist/hifi into ssao
Added toggle for ambient occlusion (defaults to off).
updates required for fervor updater with Qt5
move checkForUpdates to menu to have option in menu
move update checking later in init, add menu option
replace appcast url with highfidelity s3 bucket link
remove unneeded package finds in interface CMakeLists