BS-6712, getPossibleUserIdsOfPendingTasks hql query optimisation, getPossibleUserIdsOfPendingTasksWithoutMemberships deleted since it is no more used
Merge branch '6.2.x' into MasterBugFixing

Conflicts:
	bpm/bonita-core/bonita-process-instance/bonita-process-instance-impl/src/main/java/org/bonitasoft/engine/core/process/instance/impl/ActivityInstanceServiceImpl.java
	bpm/bonita-core/bonita-process-instance/bonita-process-instance-model-impl/src/main/resources/org/bonitasoft/engine/core/process/instance/model/impl/hibernate/process.instance.queries.hbm.xml
move hql queries tests to dedicated module
move hql queries to dedicated module