Update to walk.js v 1.1

Revised code structure (see /libraries for new files), walk animation
completely overhauled (now using geometric wave generators, Fourier
synthesis and Butterworth LP filtering for selected motion curve
construction), redesigned sidestepping animations, tweaked flying
animations, decreased maximum walk speed in Interface to more natural
human value, improved Hydra support, added support for Leap motion,
animation file sizes optimised, cleared out code used to work around now
fixed bugs, lots of minor tweaks and improvements. walk.js is now under
100,000 characters, but I had to use tabs instead of 4 spaces to get it
below the threshold.
Mirror/warning fixes.
This actually seems to work differently on OS X versus Linux.
Fix for audio toolbox.
Trigger fixes.
Fix for invalid projection matrix on startup.
Merge branch 'master' of https://github.com/highfidelity/hifi
Merge branch 'master' of https://github.com/highfidelity/hifi
Linux warnings fixes.
Revert "Fix build warning"
Merge pull request #3763 from highfidelity/revert-3762-fix-build-warning

Revert "Fix build warning"
Revert "CR for Job #20140 - Add Overlays.getTextWidth"
Merge pull request #3764 from highfidelity/revert-3759-20140

Revert "CR for Job #20140 - Add Overlays.getTextWidth"
Revert "Revert "Fix build warning""
Formatting changes to walk.js 1.1

Minor formatting changes for HiFi coding standard compliance
Merge pull request #3765 from highfidelity/revert-3763-revert-3762-fix-build-warning

Revert "Revert "Fix build warning""
Switch members in EntityItemProperties to hack around corruption bug
Merge pull request #3766 from Atlante45/corruption_bug

Switch members in EntityItemProperties to hack around corruption bug
fix a bug produced by not setting deleted var to NULL
Merge pull request #3767 from birarda/plugs

fix a bug produced by not setting deleted var to NULL