Simple test backend

Takes a port and identifier string.  Listens on the given port, and
resturns the identifier string for any request
Spec helpers for starting/stopping backends.

and a test that hits a started backend.
Add test running against the router.

This currently relies on data manually inserted into the database
Insert routes, and hook everything up.
Support specs using either source or compiled router.

Switched by env var.  This will ensure that the binary that the tests run against in jenkins is the same binary that ends up in the deb.
Remove compile.sh

It's been superseded by the build_gopath script.
Don't retry infinitely when spawning things.
Merge pull request #6 from alphagov/initial_functional_test

Initial functional test

[Delivers #58251192]