HPCC-11958 Add Roxie State check to preflight

The similar logic in ecl-roxie is used by this fix to
retrieve and format information about roxie state (hash).
The information is displayed inside ECLwatch preflight
page (a new column 'Roxie State'). WsMachine thread pool
is used to improve the performance of retrieving the
information.

Signed-off-by: wangkx <kevin.wang@lexisnexis.com>
That does use context, but not from this object. it can be removed from here... and context can be removed as a parameter to  getRoxieStateInfo.