remove warning: unused variables
fix warnings about signed/unsigned comparisons
fix warning about out of order initialization
remove warning about uninitialized variables
merge upstream/master > andrew/say-no-to-warnings
Fix running scripts scrollbar and add scrollbar to list of all scripts
Merge pull request #3106 from ctrlaltdavid/19823

Code Review for Job #19823
merge upstream/master into andrew/say-no-to-warnings

Conflicts:
	interface/src/ui/ApplicationOverlay.cpp
	libraries/audio/src/AudioRingBuffer.cpp
remove warning about signed/unsigned comparison
remove warnings about signed/unsigned comparisons
Merge pull request #3110 from AndrewMeadows/say-no-to-warnings

remove warnings
Merge branch 'master' of https://github.com/highfidelity/hifi into replace_qnetworkaccessmanager
Added forgotten sendCustomRequest Method + comments
Switched call to setCache to invokeMethod