Unicorn initialization script

Handles correct starting, restarting, stopping and reloading.

Based on Eric Wong's [example script](http://bogomips.org/unicorn.git/tree/examples/init.sh)

Modified to handle workers starting up from [this patch](https://gist.github.com/ktheory/2988633)

I'm not very happy with the where this script is being placed.  Any recommendations?  Also, can anyone point me to better upstart docs?  I feel that this should be incorporated there but I don't fully follow how Rubber uses it.