Sentinel Routine Querying Tool Documentation

Pull request #1445: Routine maintenance

Merge in SENTINEL/sentinel-routine-querying-tool-documentation from routine_maintenance to master

* commit '11d55083f25b1c148c6eaaf4cb0dbb0c5096bd3a':
  DEV-35075; fixed misspelling for preg_outcome variable
  DEV-35075; added PRE_OUTCOME variable
  DEV-35011: changed ENRDAYSAFTIND to REQDAYSAFTIND in file 030
  DEV-35003: changed MAXEPISODEDUR to MAXEPISDUR in file 796
  DEV-35003: changed change MAXEPISODEDUR to MAXEPISDUR in file 435