use updated user and group attributes when creating plugin directories
Merge pull request #7 from cwjohnston/fix-plugin-dir-ownership

use updated user and group attributes when creating plugin directories
rework init script template selection using value_for_platform_family
add a which method to test helpers and use it for locating newrelic_plugin_agent executable
let nrsysmond be installed on fedora also
remove Fedora support from pull-request 6
and use user:group variables in initscript
set updated_by_last_action in user provider