Add 'play' method to allow for playing of sounds.

There is no ability to send sounds to Campfire directly from the
response message object. However, using Campfire you simply "/play
sound".

Add this ability to the `Adapter` and the provided default adapter
implementations. It is added to the `Shell` adapter to allow for an
easier time at testing / debugging scripts using the local shell.

Add to the `Campfire` adapter as this is the core place where it
can be used.
Killed off wikis, uploaded to s3

http://atmosdotorg.s3.amazonaws.com/hubot.wiki.tar.gz
Update to coffee-script 1.6.1
Add default play implementation on Adapter.

This will log a warning if the loaded adapter does not implement the
`play` function and a script calls it.
Merge branch 'campfire-play-patch' of https://github.com/cupakromer/hubot into cupakromer-campfire-play-patch
Update tomdoc formatting
Remove warning and shell play function
Exit on hubot-scripts.json errors
Exit on external-scripts.json errors
Exit on errors encountered while loadFile
Exit when failing to load external scripts from npm
Exit when adapter can't be loaded
Merge pull request #432 from github/exit-on-errors

Exit on errors during startup
release 2.4.8
Add ability to listen for topic changes

Adapters must specifically implement receiving TopicMessage when they handle a
changing topic.

Closes #349
Update README with formatting changes

Also remove the section of running the tests
Bump npm package versions
Fix require
Clean up Brain
Clean up Listener