[third_party] port latest changes from QtAwesome
enabeld travis ci email notifications
fix a typo
Merge pull request #149 from Chilledheart/patch-1

fix a typo
Merge pull request #146 from Chilledheart/qtawesome_backport

[third_party] port latest changes from QtAwesome
DEBUG: try to fix icons problem on HDPI screens
try fix button icon size
try drawPixmap within an rect
tmp
implementation of isHighDPI for cocoa
subst fontawesome icons with png icons

fontwsome icons do not work in retina display
port to qt5
[build] enhance genapp.sh