downgrade react-router to v3.0.0 and a11y to v5.1.1 (#99)
downgrade react-router to v3.0.0 and a11y to v5.1.1 (#99)

* Downgrade react-router version to 3.0.0 to deal with errors causing blank pages

Yelp/beans,Yelp/beans,Yelp/beans