Minimum required Qt lowered to 5.5.0
Added CI for Qt 5.5.1 build
Increased C++ standard to C++14
Fixed use of spaces instead of tabs
Removed duplicate constructors
Number of warnings like this has been fixed
DockWidget.h:62:9: warning: class 'DockContainerWidgetPrivate' was previously declared as a struct [-Wmismatched-tags]
Also in ads_globals.cpp Clang didn’t like how that code setup so I changed it to what I think is the correct way. This would be good to get verified.