[New module] Module Synthseg

[anroy1]

Filling your PR description

add synthseg segmentation module from freesurfer 7.4.

List test packages used by your module

• heavy.zip

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• Create the tool:
  • Edit ./modules/nf-scil/<category>/<tool>/main.nf
  • Edit ./modules/nf-scil/<category>/<tool>/meta.yml
• Generate the tests:
  • Edit ./tests/modules/nf-scil/<category>/<tool>/main.nf
  • Edit ./tests/modules/nf-scil/<category>/<tool>/nextflow.config
  • Add test data locally for tests with the fork repository
  • Generate the test infrastructure and md5sum for all outputs
• Ensure the syntax is correct :
  • Check indentation abides with the rest of the library (don't hesitate to correct others !)
  • Lint everything. Ensure your variables have good names.

[AlexVCaron]

Another great PR ! Not much to say, everything is syntax and wording. It,s going on well, once done LGTM !

[AlexVCaron]

Two little things to fix. Also, add the segmentation in the module's outputs and test it's md5SUM as well. We'll know then if mri_synthseg is the source of the problem.