Be able to change library state of a paper on its respective page

[hexhowells]

In order to change the state of a paper in the library (from 'To Read' -> 'Reading' for example) you need to go into the library, find the paper, and change the state there. However, if you started or finished reading a paper, you likely accessed the paper from the paper' page, thus you should be able to update the papers state in the library from that page as well.

Should be easy to implement since the API calls are already there, could even export the dropdown menu from the library into a new component and just use that.