two possible crash fixes
Fixes for eyes rolling back in head, macaw head without mapping file.
Merge pull request #1027 from ey6es/master

Fixes for eyes rolling back in head, macaw head without mapping file.
Merge pull request #1025 from ZappoMan/voxel_render_modes

two possible crash fixes
make sure username is not empty before requesting faceMesh
Merge branch 'master' of github.com:worklist/hifi into nameserver
pack the UUID with the avatar data
pass UUID from data-server to avatar-mixer