update to babel 6, add semicolons after static props to conform

[bdefore]

Note that currently with the latest on npm 0.2.2, you'll get the following warning:

→ npm install --save async-props

npm WARN EPEERINVALID async-props@0.2.2 requires a peer of react-router@^1.0.0 but none was installed.

And if setting your dependency to rackt/async-props you'll get another error if you're on Babel 6:

d4: ~/code/universal-redux (async-props)
→ npmi

> async-props@0.2.2 postinstall /Users/d4/code/universal-redux/node_modules/async-props
> node ./npm-scripts/postinstall.js


> async-props@0.2.2 build /Users/d4/code/universal-redux/node_modules/async-props
> babel ./modules --stage 0 --loose all -d lib --ignore '__tests__'

SyntaxError: modules/AsyncProps.js: A semicolon is required after a class property (148:3)
  146 |     Component: func.isRequired,
  147 |     routerProps: object.isRequired
> 148 |   }
      |    ^
  149 |
  150 |   static contextTypes = {
  151 |     asyncProps: object.isRequired

These changes update the core library to use Babel 6 for compilation and fix the static props error, but until another npm publish happens you can set your dependency to bdefore/async-props#babel6-support

[taion]

Transpiled modules don't work that way – you're not supposed to import from modules/ directly. If you need to install from GitHub, transpile the package using its own toolset first.

[bdefore]

right but at this point those are your only options for working with react router 2 with async-props until a new version is published. this PR is an attempt to fix that.

[taion]

Check it out locally, run npm i && npm run build, then install from there. That's how you normally work with repos that use transpiled code anyway.