general clarification, less theLuggage importance

Bumped OS compatibility, clarified path to script, added wording around
processing stuff(since nothing is explicitly ‘defined’ besides
placement), added wording for testing/ad hoc addition of items
requiring specific perms/ownership, updated link to munki project code
Merge pull request #5 from arubdesu/docs-tweak

general clarification, less theLuggage importance