Glob files to include in gem more effectively.

I was receiving a ENOENT when trying to create an RPM repository
due to a missing template (primary.xml.erb to be specific). I
looked in the gem lib and the templates dir only had the 
deb_release.erb installed. Using Dir.glob grabs all the necessary
files.
Merge pull request #26 from imeyer/master

Glob files to include in gem more effectively.