Update README.

The README was the one generated by the *berks* utility.  This update
removes much of the boilerplate and adds some actual content.  Also
added a LICENSE file that I somehow forgot to commit before.
Correct .tailor file.

The tailor configuration ignored the first two file sets.  Tailor
requires file sets to have unique names.  This commit assigns explicit
names to each of the file sets.
Rename "default" recipe to "server".
Install python.
Install python virtual environment.

The devpi server will be installed into a python virtual environment in
the /opt tree.
README.md: Line wrap the "Contributing" section.
Install devpi-server package.
Create privilege separation user.
Create administrative group.
metadata.rb: Add recipe statement.
Add support for Enterprise Linux.

Enterprise Linux was already supported but I made it official by
documenting it and testing it on CentOS.
Merge branch 'feature/server-recipe' into develop
Rakefile: Clean up VMs in maintainer-clean.
Guardfile: Add guard-kitchen plug-in.

The guard-kitchen plug-in from Opscode uses test-kitchen to converge and
verify your cookbook as you modify it.  It does this by starting the
vagrant boxes when guard initializes (via `kitchen start`) and
converging or verifying as your recipe changes.
CHANGELOG.md: Prepare for 0.1 release.
Merge branch 'release/0.1'