Refine tool buttons of main window,.Font by  fontawesome.io

Font Awesome gives you scalable vector icons that can instantly be customized — size, color, drop shadow, and anything that can be done with the power of CSS.
Merge branch 'dev' of github.com:QSanguosha-Rara/QSanguosha-For-Hegemony into dev

Conflicts:
	src/dialog/mainwindow.cpp