Merge pull request #66 from nongxiaoming/master

fix the export function name error of rtgui_graphic_driver_is_vmode func...
dc: add gradient rect support
Code cleanup
Merge remote-tracking branch 'origin/master' into gradient
button: code format and call widget_update instead of raw theme draw
export more symbles
window: clear the CLOSED flag in win_show
filelist_view: clean on_changed on constructor
Remove event dump.