Issue #84: Document *_package_name usage

Document that setting false for package_name prevents the modules from
managing the package.
* Fix error in template if rsyslog_version fact is not present
Merge pull request #90 from treydock/master

Fix error in template if rsyslog_version fact is not present
Merge pull request #89 from yasn77/document_package_name_usage

Issue #84: Document *_package_name usage