<oo-accept-broker> Fixes to generalize over RHEL and Fedora

Wrap ruby and bundler in functions to achieve platform-appropriate
invocations (scl vs. standard), detect scl presence
<oo-accept-broker> cleanup, documentation comment

Comment explaining why ruby output in load_application_values is run
through tail
Merge pull request #2182 from dobbymoodge/oo-accept-broker

Merged by openshift-bot