[common, utils] common clean up, rename QtcPixmap to QtcImage
[gtk2] clean up, remove 2.12 support
[qt5] do not use WA_TranslucentBackground on QMenu and QComboBoxPrivateContainer.
[qt] include clean up
[common] clean up
[utils/timer] add timer
[utils/timer] use ForceLog
[utils/macros] document
[gtk, utils] clean up
[utils/atomic, utils/color] document atomic, color clean up
[utils] simplify default argument
[gtk2] minor tweak
[utils] version clean up.
[utils, gtk2] format, fix qtcNew