Merge pull request #4885 from jakesmith/hpcc-3315

HPCC-3315 - Spot cluster 'realCluster' mismatch

Reviewed-By: Richard Chapman <rchapman@hpccsystems.com>
HPCC-8245 - Smart Lookup Join

Implementation of Lookup Join that on OOM fails over to a
hash distributed lookup join, then if that OOM's, fails over to
a regular fully distributed(both sides) local join.

Signed-off-by: Jake Smith <jake.smith@lexisnexis.com>
HPCC-8245 - Clear up a few things

1) bug, race between 1st/2nd broadcasters on different slaves
2) Ensure all members initialized in constructor
(move some things from init() to constructor in the process)
3) Clear up tabs vs spaces
4) Unify on one createLookupJoinSlave() method and use TAK type
5) Add #TEST_FAILOVER_ defines
6) Comment in JFsmart usage

Signed-off-by: Jake Smith <jake.smith@lexisnexis.com>