Code Review :)

Lots of changes to agent:
 - A couple refactors to streamline duplicate code
 - Replaced old Twitter class with new Twitter class
 - Changed how settings work
   - Users now need to make a web request to their agent the first time they run the code:
     https://agent.electricimp.com/{agentUrl}/settings?name={nameValue}&attn={attnValue}

A few really minor changes to device code:
 - Added "= null" to a couple variable declarations
 - Removed InputPort code
 - Changed "server.expectonline + imp.deepsleepfor" to "server.sleepfor" which is equivalent to the two calls combined
 

NOTE: I also noticed the device code uses a variable called 'i2cRetryPeriod' that is never defined.