I've added HR support

[morksinaanab]

Hey,

I've added HR support. I'm new to pull requests and how that works, how would i do that?

I've done it here: http://github.com/morksinaanab/react-native-easy-markdown

[juiceo]

@morksinaanab please look here for instructions on how to create a pull request: https://help.github.com/articles/creating-a-pull-request-from-a-fork/

A few things you could fix before creating a PR:

• Please close the View tag since it has no children: instead of <View></View> do <View/>
• I would discourage using width: '100%', you can achieve the same result with alignSelf: 'stretch'
• No need to give renderLine a third parameter in renderNode (Utils.concatStyles...) since it is not being used in renderLine.

Thanks for contributing, looking forward to your PR!