update for API v2

NOTE: I found this API key in another project that uses.  Unclear on sourcing.
Caveat Emptor.
finish implementing shut-down behavior
flesh out error handling

Don't absorb all exceptions silently.  Ctrl-C now works.

Adds uh-oh code path to differentiate actual errors from when it fails to
understand the statement (i.e. the sorry code-path).
comment out some spurious mic reinitializations

Leaving in there as a comment on the off chance that they're there for a
reason.
print what Jarvis heard

Used this for debugging.
fix copypasta
no need to reimplement random.choice
use native sound player on Darwin
update dependencies list
add author info
Merge pull request #2 from jvantuyl/master

Batch of Updates
Add requirements.txt and update the README for a note on mac installation
Merge pull request #3 from issackelly/master

Add requirements.txt and update the README for a note on mac installation
Add Issac Kelly to CONTRIBUTORS