* fixed #3800

https://github.com/ElemeFE/element/issues/3800 fixed

* Switch:fix switch will blink when render in server beause its default width is 0.

* filled gaps in translation

* Update pl.js

* Card: add shadow attribute

* Card: fix test file

* Card: modify shadow class

* Card: modify test file

* Card: fix props

* Button: add circle attribute

* test: modify button round

* Button: update docs for round & circle

* Button: fix disabled docs

* Button: fix button margin

* Button: fix button margin

* MessageBox: should allow showInput when message is empty

* MessageBox: no confirm when inputType === 'textarea'

* MessageBox: hide status when message is empty