[new feature] add i18n support (#310)

* fix: Tabbar icon line-height

* [new feature] progress add showPivot prop

* [new feature] TabItem support vue-router

* [new feature] update document header style

* [Doc] add toast english ducoment

* [new feature] add i18n support

* feat: Extract demos from markdown

* feat: Base components demos

* [new feature] complete demo extract & translate

* [fix] text cases

* fix: add deepAssign test cases

* fix: changelog detail

* [new feature] AddressEdit support i18n

docs/markdown/en-US/notice-bar.md

@@ -0,0 +1,58 @@
+## NoticeBar
+
+### Install
+``` javascript
+import { NoticeBar } from 'vant';
+
+Vue.component(NoticeBar.name, NoticeBar);
+```
+
+### Usage
+
+#### Basic Usage
+
+```html
+<van-notice-bar
+  text="Only those who have the patience to do simple things perfectly ever acquire the skill to do difficult things easily."
+  leftIcon="https://img.yzcdn.cn/1.png"
+/>
+```
+
+#### Disable scroll
+
+```html
+<van-notice-bar :scrollable="false">
+  Only those who have the patience to do simple things perfectly ever acquire the skill to do difficult things easily.
+</van-notice-bar>
+```
+
+#### Mode
+
+```html
+<van-notice-bar mode="closeable">
+  Only those who have the patience to do simple things perfectly ever acquire the skill to do difficult things easily.
+</van-notice-bar>
+
+<van-notice-bar mode="link">
+  Only those who have the patience to do simple things perfectly ever acquire the skill to do difficult things easily.
+</van-notice-bar>
+```
+
+### API
+
+| Attribute | Description | Type | Default | Accepted Values |
+|-----------|-----------|-----------|-------------|-------------|
+| mode | Mode | String | `''` | `closeable` `link` |
+| delay | Animation delay (s) | Number | `1` | - |
+| speed | Scroll speed (px) | Number | `50` | - |
+| scrollable | Whether to scroll content | Boolean | `true` | - |
+| leftIcon | Image url of left icon | String | - | - |
+| color | Text color | String | `#f60` | - |
+| background | Background color | String | `#fff7cc` | - |
+
+
+### Event
+
+| Event | Description | Attribute |
+|-----------|-----------|-----------|
+| click | Triggered when click notice bar | - |