Implemented rtl layout support

[saeedrahimi]

Hi there.
I've added rtl layout support to this component.
changes the tab direction with direction='rtl' property

• Added rtl demo
• updated readme
• fixed issues mentioned by @zombieJ in stale pull request

[vercel]

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🔍 Inspect: https://zeit.co/react-component/tabs/7crz21fiq
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[coveralls]

Coverage increased (+0.05%) to 72.576% when pulling e80a75c on saeedrahimi:support-rtl into 0c8ed2d on react-component:master.

[zombieJ]

Lint failed: https://travis-ci.org/react-component/tabs/jobs/596954342

[zombieJ]

Still failed. You can view coverage link to see the coverage diff: https://coveralls.io/builds/26294799

[zombieJ]

Should we use context to get the direction instead of both Tabs and InkTabBar should have direction props?

[saeedrahimi]

tabs/src/Tabs.js

Lines 182 to 191 in 9dcbe12

	const tabBar = React.cloneElement(this.tabBar, {
	prefixCls,
	navWrapper,
	key: 'tabBar',
	onKeyDown: this.onNavKeyDown,
	tabBarPosition,
	onTabClick: this.onTabClick,
	panels: props.children,
	activeKey: this.state.activeKey,
	});

I found that i can pass direction to all kind of tab-bars in this part of code

[saeedrahimi]

added.

tabs/src/Tabs.js

Line 191 in ca6d50f

direction: this.props.direction,

[saeedrahimi]

@zombieJ all done

[zombieJ]

LGTM
@afc163 help to double confirm

[saeedrahimi]

@afc163 , @zombieJ could you approve these changes? I need them in ant-design RTL implementation

[zombieJ]

+ rc-tabs@9.7.0