Fix process bug

When the gem was split into mounted/non-mounted files, the CLI process
command was broken for any app that used the #mount DSL method.
Fix annoying line break

:beer:
Relax dependencies in gemspec

Don't think there was any reason to be hard about being >= patch level
releases. Famous last words...
Add Rails usage example

Strikingly similar to Sinatra!
Update Sinatra example

To match better wording / simpler CSS in Rails example.