introduces bandwidth meter / dialog
improves bandwidth meter layout / simplifies & fixes rendering
tightens bounding issues for bandwidth meter's scale indicators
Merge branch 'master' of git://github.com/worklist/hifi into 19377

Conflicts:
	interface/src/Audio.cpp
Merge branch 'master' of git://github.com/worklist/hifi into 19377
keeps audio from crashing when sound device is unavailable
combined bandwidth display at automatic scale
polishes bandwidth meter
adds code to show bandwidth details upon click and adds a checkbox to the menu to set visibility of the bandwidth bars
increases height of bandwidth meters by 8 pixels
Bandwidth meter: Bytes -> bits, number formatting (colors, digits, aligment) on dialog
Merge branch 'master' of git://github.com/worklist/hifi into 19377
makes bandwidth details dialog properly close (and reopen) on ESC key
improves defaults and inline documentation of bandwidth meter layout constants
Merge branch 'master' of git://github.com/worklist/hifi into 19377
introduces named constants for bandwidth meter channel indices / max. drag length
Merge pull request #600 from tschw/19377

Code Review for Job #19377
prevents voxel data from being sent or received (read: requested) when voxel rendering is disabled
also adds a menu option under "Tools" to enable/disable the Oscilloscope