Rebuild samples

Updates!

* hello-world, server-with-links, ring-middleware were straightforward.
* template server pages now produce identical html and have been updated to recent versions
* cors sample was completely overhauled.

With the exception of `hello-world`, changed all of the `main` functions to follow this structure:

```clojure
(-> service/service
    server/create-server
    server/start))
````

Other stuff:

* Removed `dev` clutter; we should consider adding a sample focused around actual development 
work processes, but with dev scattered about, each sample loses focus.
* Moved source files, templates, static files, etc. into `resources/` directories.
* Updated documentation where required.
This actually changes what you're doing.  You're applying interceptors AFTER the endpoint definitions, that's not what you want.  You want the interceptors to be run as part of the interceptor chain FOR the endpoints.