Feature library

Enzymes work. Feature library backend works. There is an add button on the front end. You can add a library but it won't show up unless you refresh the page. I have tried to fix this and don't know why. Selecting a different library does not correctly update the shown features Basically, not all of feature libraries works, but it's stable and nothing is broken. I'll try to fix it after getting some sleep. :(

Adds #39, and #37