Rakefile: Fix unit-test task.

The unit-test task really should clean up after itself by removing the
vendored cookbooks.  This commit makes it so.
Vagrantfile: Use single quotes consistently.
FEATURES.org: Add feature tracking via Orgmode file.
Guardfile: Add ignore for dot files.
Add simple supervisor recipe.

This commit includes a testing cookbook that patches the opscode
supervisor cookbook since it does not install the daemon control scripts
on RHEL-based systems.
recipes/server: Set devpi home directory.
recipes/server: Create server data directory.
recipes/supervisor: Add devpi-server job.
recipes/supervisor: Add server_port attribute.
Merge branch 'feature/daemonize-with-supervisor' into develop
metadata: Add supervisor recipe.
CHANGELOG.md: Prepare for 0.1 release.
README: Update description of supervisor recipe.

The description omitted that it assumed the presence of the
*devpi::server* recipe in the run list.
CHANGELOG: Prepare for the 0.2.0 release.
Merge branch 'release/0.2.0'