remove unused cruft from Model class API
Model now knows its bounding radius
Adding per-palm penetration accumulator
Hands can collide with avatar head again
Merge upstream/master' into shapes branch
Merge upstream/master

Conflicts:
	interface/src/avatar/MyAvatar.cpp
degrees instead of radians for head lean deltas
Merge upstream master into "shapes" project
fixing signed/unsigned comparison
improved index sanity checking
Fix for bug with reliable messages.
Merge branch 'master' of https://github.com/highfidelity/hifi into metavoxels

Conflicts:
	interface/interface_en.ts
Updated translations.
Merge branch 'master' of https://github.com/highfidelity/hifi into metavoxels
Merge branch 'master' of https://github.com/highfidelity/hifi into metavoxels
Merge branch 'master' of https://github.com/highfidelity/hifi into metavoxels
Merge branch 'master' of https://github.com/highfidelity/hifi into metavoxels
Working on streaming metadata.
Optional hash/full metadata streaming for QObjects.
Cleaned up the preprocessor definitions.