Create providers directory; Markdown provider

src/core/components/layout-utils.jsx

@@ -1,13 +1,10 @@
 import React, { PropTypes } from "react"
 import OriCollapse from "react-collapse"
-import _Markdown from "react-remarkable"
 
 function xclass(...args) {
   return args.filter(a => !!a).join(" ").trim()
 }
 
-export const Markdown = _Markdown
-
 export class Container extends React.Component {
   render() {
     let { fullscreen, full, ...rest } = this.props