Difficult to understand the different profiles

[EliseCos]

Description of problem

The different profiles are not very clear in the documentation or in the figure. It is difficult to understand which steps are executed for each profile. In particular, which profile is used when no profile is specified.

[AlexVCaron]

To address this, I think we should better stratify the profiles by role. Profiles do one of four things. Either :

1. Change the execution environment. Activates global configuration (aka conda, virtualenv, npm), containerization (aka docker, apptainer, podman) or acceleration (aka GPU, TPU or other newer chip)
2. Change the process scheduling (aka local machine, SLURM, AWS)
3. Change the process sequence (aka disable/enable parts of workflows/subworkflows)
4. Change the process configuration (aka predefined configurations for multi-shell DWI, PGSE sequences or additional sidecars)