Libraries updated.

[ericwooley]

@ralfgerlich

I updated the libraries, to get rid of some really bad XSS stuff that was probably possible.

Bootstrap has been updated to 3.4.1, underscore to 1.13.6, jquery to 1.12.4.

Code mirror doesn't have anything real bad, so I just left it alone, since I think that might be a huge pain to update.

I tested out various functionality, and everything seems to be working. But LMK if you have issues due to the upgrades.

[ralfgerlich]

@ericwooley Thank you for that. So far everything seems fine.