Removed the get_versions.py script as an entry point. For some reason this is messing up with the macports build

Reordered the requirement list

Changed the file bootstrap.py to bootstrap-buildout.py

Checked the existence of pkgtools in the environment

Added the package documentation for the bob.db.atnt bob.db.wine bob.db.base bob.db.mnist bob.ip.facedetect bob.ip.opticalflow