CBRAIN's fsl_sub to submit all subtasks at once

[prioux]

The current 'patch' to fsl_sub to make it work with CBRAIN works like this, when an arrray of tasks need to be submitted:

• loop through each task:
  • create a .json file
  • wait up to 5 minutes for a .cbid file

Instead of that, loop through all the tasks, create all the .json files, then wait for all the .cbid files to appear.