====== Idea ======

The idea here is to allow someone that runs a "timesharing=*,*" job, to run a new job on the resource but with the more restrictive specification: "timesharing=user,*", if no "timesharing=*,*" jobs are running from other users.

With the semantic of the Digitalis platform where:
  * -t shared <=> -t timesharing=*,*
  * -t exclusive <=> -t timesharing=user,*
This would allow a user to place a exclusive slot on top of a larger shared slot if he is alone on the machine.


====== Technical details ======
Currently, the 4 timesharing specifications are handle at a same level:
  * timesharing=*,*
  * timesharing=user,*
  * timesharing=*,name
  * timesharing=user,name
No hierarchy like timesharing=*,* < timesharing=user,*.

Implementing such a "hierarchical management" in the gantt data-structure mechanisms could allow that feature. 


**moved to https://github.com/oar-team/oar/issues/93**