FSL : harmonization with SPM and cleaning up the project structure

[thomasbtnfr]

Important note: this PR is built on https://github.com/bids-standard/BEP028_BIDSprov/pull/85. https://github.com/bids-standard/BEP028_BIDSprov/pull/85 must be reviewed and merged first

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The purpose of this pull request is to implement the same processes on the FSL parser as those in SPM. This includes:

• Use of UUID
• Use of a mapping for labels via a different json file than SPM
• SPM and FSL now share the same default graph and the same CONTEXT_URL. In addition, all the functions shared by the 2 parsers have been gathered in a utils file. Unit tests have been written for these functions.
• The overall structure of the project was reviewed. It is now structured as follows:
  • bids_prov
    • fsl
    • fsl_config.py (specific configuration for FSL which is not in the utils file
    • fsl_labels.json
    • fsl_parser.py
    • spm
    • spm_config.py
    • spm_config.yml
    • spm_labels.json
    • spm_parser.py
    • tests
    • fsl and spm unit tests + graph inclusion
    • utils.py
    • visualize.py
  • results
  • .github
  • and some configuration files...

In addition, this pull request reworks the reading of FSL log files. Indeed, in accordance with this issue, some lines were not read such as those containing numbers that stopped the reading for a particular step. Furthermore, lines starting with did not find were read and according to our discussion of 17/01, they should not be read. This has been corrected.

[thomasbtnfr]

Conflicts have been resolved. The PR is ready to be reviewed.

[cmaumet]

(Note: I am merging this now so that I can more easily review the FSL examples --- @thomasbtnfr when you can would be great if you can address the two tiny comments above, thx!)