refactor tab-navbar border color
fix btn doc bug
set form xfat fontsize 14px
change tooltip type normal -> default
update progress: use background instead of border
add progress bar text
update index
add discuss
Merge remote-tracking branch 'sui/dev' into dev

Conflicts:
	docs/templates/buttons.jade
	docs/templates/progress.jade
	docs/templates/tooltip.jade
	less/forms.less
	less/progress-bars.less
	less/tooltip.less