Implement test for removing a resource
Test remove via GET
Add test for removing a resource via id
Tidy up by separating assertCount
Sketch out middleware API

The idea is that there can be both pre- and post-handlers. These may be
used to perform tasks such as authorization (pre) and triggers (post).
Add some initial hooks for middleware architecture
Sketch out middleware loading
Hook up post middleware
Hook up prehandlers
Add some stubs for auth tests
Remove middleware related aspects
Add a test runner