299 doc restructure

Here's my first stab at this.

The idea is to trim the main README down to "everything you need to know in 5 minutes", and then break out the rest into topic documents.
Maybe make the file names bold. Also escape the `_` in the names to avoid unintended italics.

Also, make the name of the module something different from `restful_example` to avoid name collisions with people doing copy & paste. Maybe `restful_custom`?

restful_example/restful_example.info :arrow_right: **restful\_custom/restful\_custom.info**.