add feedback btn  and js css
Merge remote-tracking branch 'qiniu/master' into add_feedback_btn
add pic
main.css
add gitignore
remove useless code
Merge remote-tracking branch 'qiniu/master' into add_feedback_btn

Conflicts:
	static/js/docs.js
test code / change btn position
Merge remote-tracking branch 'qiniu/master' into add_feedback_btn

Conflicts:
	_layouts/docs.html
Merge remote-tracking branch 'qiniu/master' into add_feedback_btn
update makefile
change to test env
Merge pull request #36 from BluntBlade/master

修正downloadToken的算法描述（#6363）。
add image
css-sprite
update css_sprite/docs.js/zendesk.js
Merge remote-tracking branch 'qiniu/master' into add_feedback_btn
update ifream url
fix the lineheight bug
Merge pull request #5 from SunLn/add_feedback_btn

add feedback btn  and js css