Properly validate tags facts options
Properly validate tags facts options

Previous to this commit, an improper
hash could have been generated if the user
input was invalid.  This commit tests
that for each tag and fact given,
the key and the value are not nil and
not empty.

16nsk/puppetlabs-cloud_provisioner,amos6224/puppetlabs-cloud-provisioner,puppetlabs/puppetlabs-cloud_provisioner,puppetlabs/puppetlabs-cloud_provisioner