anchor.diff:  ----
       <pillarSwapMoveSelector>
         <subPillarType>SEQUENCE</subPillarType>
  -      <subPillarSequenceComparatorClass>...</subPillarSequenceComparatorClass>
  +      <subPillarSequenceComparatorClass>org.optaplanner.examples.nurserostering.domain.ShiftAssignmentComparator</subPillarSequenceComparatorClass>
         ... <!-- Normal selector properties -->
         <pillarSelector>
           <entitySelector>
  -          <entityClass>...Lecture</entityClass>
  +          <entityClass>...ShiftAssignment</entityClass>
             ...
           </entitySelector>
           <minimumSubPillarSize>1</minimumSubPillarSize>
  
positive.code: 
  A sub pillar is a subset of entities that share the same value(s) for their variable(s). For example if queen A, B, C and D are all located on row 0, they are a pillar and `[A, D]` is one of the many sub pillars.
  
  There are several ways how sub pillars can be selected, driven by `subPillarType` property:
  
  - `ANY` (default) will select all possible sub pillars.
  - `SEQUENCE` will limit selection of sub pillars to <<sequentialSubPillars,Sequential sub pillars>>.
  - `NONE` will never select sub pillars.
  
  If sub pillars are enabled, the pillar itself is also included and the properties `minimumSubPillarSize` (defaults to ``1``) and `maximumSubPillarSize` (defaults to ``infinity``) limit the size of the selected (sub) pillar.
  
  
negative.code:     </pillar...MoveSelector>
  ----
  
  In this case, the entity being operated on need not be `Comparable`. The given `subPillarSequenceComparatorClass` is used to establish the sequence instead. Also, the size of the sub pillars is limited in length of up to 1000 entities.
  
  [[chainMoveSelectors]]
  === Move selectors for chained variables
  