Cleanup exception message for retry on index metadata not found exception, pass through TenantId attribute value if present, clear metadata cache for htable explicitly if index metadata not found
Make IndexMaintainer thread safe
Small cleanup to propgate errors

Also, adding some more fixes around releasing locks on stop to
enable fast shutdown.
Bug fix for isBytesComparableWith for VARBINARY and BINARY, new test for DECIMAL to DOUBLE comparison
Really, really make IndexMaintainer thread safe this time by removing dataRowKeyLocator member variable and instantiating in buildRowKey instead
Merge pull request #460 from jyates/propagate-index-errors

Small cleanup to propgate errors