Historical logs in UI

Code is almost as-is from @Utkarsh2012, apart from some changes to make it work with code that has changed since he forked it.

I tried to divide the commits into backend pieces first, (then some fixes) then front end. All existing tests pass this build on my machine.

I'm not sure how important it is, but eventually paginating the results may be useful, because right now it will pull the entire run history. That's probably for another pull request another day?

For issue #38