Ship known params in jenkins ship

This commit updates the jenkins ship task to write the current build parameters
(e.g., distribution_server, version(s), etc.) to the 'pkg' directory before
shipping, so that they are shipped out to our artifacts directory. This file
will later be used in our promotion workflow.

Signed-off-by: Moses Mendoza <moses@puppetlabs.com>
Merge pull request #210 from MosesMendoza/RE-322/master/ship_params

Ship known params in jenkins ship