Start of a debian package for charmstore

PR:
1. Edit buildpackage.sh and change the last line to a PPA to which you can write. 
2. Make sure you have DEBEMAIL set for signing.
3. Run sh buildpackage.sh
I am not a deb packaging expert, but does this create a config.yaml file in /etc?
Could we make it something like /etc/charmstore/config.yaml instead?