Minor update to Modulefile: we actually need vcsrepo v0.2.0 

In PR #1, I said "vcsrepo automatically requires the "git" package", but that feature was introduced in an commit that wasn't in version 0.1.2 (the latest version at the time). Fortunately, the vcsrepo guys [just released version 0.2.0](http://forge.puppetlabs.com/puppetlabs/vcsrepo/0.2.0), which does have that commit. This updates Modulefile to reflect that dependency.