[changelog] 2.0.0

[new feature] ActionSheet: add click-overlay event

[bugfix] Switch: incorrect activeColor when use activeValue

[improvement] Uploader: optimize code

[bugfix] Icon: should support render local image

Merge branch 'dev' of https://github.com/youzan/vant into dev

[new feature] Card: add bottom slot

[Doc] update README.md

�[bugfix] Pagination: should not emit change event when total-items c…

…hanged

[Doc] add doc version tip