status log UI for search/browser/revocation

[jchartrand]

Create a react app that allows browsing/searching the status log, and provides a 'revoke' button for every returned entry in the log.

Would probably need/want to add a search endpoint to the status-service.

This would be another service that runs in the docker compose for a given issuing setup. We'd publish it to docker hub.

Might call it status-log-ui

It should work with either the status-log-mongo or status-log-github since in either case the UI would just be calling API endpoints that are common across the two implementations. The ui in fact wouldn't need to know what implementation was being used.

[alexfigtree]

@jchartrand Thinks we may need to consider a separate log