React tables

I've moved the Students table over from using FilterTable/Prototype to React.js. This is better for several reasons, but the biggest is probably speed. Constructing the table is no longer done one student at a time and server-side, but instead client-side and in one batch. I've also created some generalized table components such as the search bar and table header so hopefully it shouldn't be that hard to define what your table row should look like and then just drop that into a table. Some work still needs to be done on that end though, which I'll probably end up doing when migrating the other tables over to React.
Why not just delete this (and app/views/users/table_row/_edit.html.erb) and test? If this needs to be deferred then we should add `TODO`.