don't look for GnuTLS from cmake
remove dependency on GnuTLS for later replacement with OpenSSL
remove GnuTLS include across repo
remove more gnutls includes
put back ssize_t definition
Merge remote-tracking branch 'upstream/master'
Made overlays thread safe for write operations, which solved a script
crash.
Merge branch 'master' of https://github.com/highfidelity/hifi
moved _sequenceNumber to OctreeSendThread
Merge remote-tracking branch 'upstream/master'
Merge remote-tracking branch 'upstream/master'
moved _sequenceNumber back to OctreeQueryNode

instead added incrementSequenceNumber() to OctreeQueryNode for
sendthread to use
Added some missing locks to make Overlays thread safe for reading as well.
Added a new lock specific to deleting, and improved safety
removed old code that was commented out

changed tabs to spaces
Merge pull request #2910 from wangyix/master

fix for skipped sequenceNumber bug in OctreeQueryNode
Merge pull request #2906 from Barnold1953/master

Write thread safety for Overlays QMaps
Merge pull request #2911 from ey6es/master

Use local viewer model for specular.