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. Install build dependencies (see README.md).
4. Run sh buildpackage.sh.
I think it is meant to be maintained. I'll ask Curtis how they maintain this. It sounds like they may have some tools.