standardize MonthView, Calendar and RangeCalendar
standardize MonthView,Calendar,RangeCalendar based on esui-flat-theme
add disabled state
modify MonthView Control
delete test img fold
Adjust some RichCalendar styles
Merge pull request #372 from zxhfighter/mywork

standardize MonthView, Calendar and RangeCalendar
standarnize pager control
1:修正codestyle；2：补漏firstText
修正firstText comment
Merge pull request #379 from bjlxj2008/3.1.0-dev

standarnize pager control
Merge branch '3.1.0-dev' of https://github.com/ecomfe/esui into 3.1.0-dev

Conflicts:
	src/css/standard/main.less
Merge branch '3.1.0-dev' of https://github.com/yankun01/esui into 3.1.0-dev