Import gpg keys before creating repos

Another forge module (https://github.com/jonbrouse/puppet-couchdb) creates a dependency on epel: 
```
class couchdb::package {
    package { 'couchdb':
      ensure  => installed,
      require => Yumrepo[ 'epel' ], 
  }
}
```
The repo resource is created before the keys are imported, so the install fails with:
```
GPG key retrieval failed: [Errno 14] Could not open/read file:///etc/pki/rpm-gpg/RPM-GPG-KEY-EPEL-6
```
The key is imported later in the run, and the next run works.  This moves the GPG import as a prereq to defining the repo.