User admin is confusing and inaccurate

[plusk]

Having just used the user admin a lot as "tellekorps, or as I will now refer to it, counting corps, the search functionality in user admin is rough. It's inconsistent, it often provides a lot of false positives, and the results jump around in order.
Additionally, the list view itself should be sortable on the various columns. Being able to sort alphabetically is crucial.

[duvholt]

Probably just need to tweak Fuse settings a bit to make the search less shit:

super-duper-fiesta/client/src/components/Admin/Users/List/index.js

Lines 76 to 81 in 35dc1da

	threshold: 0.6,
	location: 0,
	distance: 100,
	maxPatternLength: 32,
	minMatchCharLength: 1,
	keys: ['name'],

I think Fuse respects the initial ordering and only performs filtering by default, but we probably sort by user creation or something silly like that.

react-table seems like a nice solution for sorting, but I'm not sure how well it will work with our custom buttons in the table.