Adding basic message processing to app.'s

I’m adding some initial code to the app.js file. This code should
really be refactored to separate classes, but I plan to do that later.
Adding initial tests

I’m adding mocha to the devDependencies and adding tests for the
inbound interpreter.
Added inbound interpreter

I wrote the inbound interpreter as well as created basic files for the
three other interpreters it calls, help, stop, and subscribe.
Merge branch 'inbound_interpreter' into development
Added test for inbound interpreter

I forgot to add a test for the inbound interpreter
Fixed a mistake in the inbound interpreter tests

Typos
Created help interpreter

I created the help interpreter and its associated test
Refactored app.js

I changed some names in app.js to be more descriptive
Merge branch 'help_interpreter' into development
Created stop interpreter

I created the stop interpreter and its associated tests
Merge branch 'stop_interpreter' into development
Created subscribe interpreter

I created the subscribe interpreter and its associated tests. This also
meant adding Redis to store subscription information.
Merge branch 'subscribe_interpreter' into development