Add a :version task to print version

This commit adds simple version tasks for printing various version types of the
project, as introspected via git describe.  We're going to use this in jenkins
to introspect the package-version to be, and pass our version along to
downstream projects.

Signed-off-by: Moses Mendoza <moses@puppetlabs.com>
Merge pull request #104 from MosesMendoza/maint/master/add_version_task

Add a :version task to print version