[functions.config] New function to check mandatory parameters

It should be smart to define and check if some parameters are set. Fail pipeline if not !
List of mandatory parameters :

• Command line parameters :
  • params-file
• Autocalculated parameters
  • n_samples
  • inputdir
  • project
  • sequencer
  • data_nature
  • run_name

If any params is not set, should use default value ?