[1100300] Update of a resource configuration sometimes takes more then 100 seconds
Given feedback from the github pull request (62), change things around
to support tighter time controls at the expense of some more memory and
complexity.
- remove the 750ms delay between checks. This was supposed to be removed in
  the first pass of changes. Slows things down in a major way, the chunking
  should keep runtime spikes in check.
- increase check frequency to every 2 minutes but drop to 10s limit on
  runtime.  Now that the 750ms delay is gone, I ran a check of the 3 RHQ
  roots (EAP server, agent, storage) in well under 3s.  The time a
  root and its members are again eligible for a check is still 1 hour
  from the time it completes it's prior check (meaning it's last child
  is checked).

TODO: Still have to update logging to DEBUG once everything else is
      cleared.
  on a specific root