getChildContext() should only return its own props

i.e the ones defined in the propTypes (typesSpec here)
Add browser testing
Add execution permissions to saucelabs script
Add Travis configuration
Credentials for yahoo repository
Use grunt-saucelabs instead of Yeti
Add necessary polyfills
Add Grunt tasks
Remove IE 7 tests
Add missing Mocha dependency
Merge pull request #16 from juandopazo/sauce

Add browser smoke tests in Saucelabs
Merge branch 'master' of github.com:athibaud/react-intl into athibaud-master
Merge branch 'athibaud-master'
Simplify getChildContext
Update Sauce Labs credentials
Update Travis badge to shields.io