Re-organizing suffix section and other improvements [WIP]

[agahkarakuzu]

• Improved PCTS for suffix
  • Added an explanation on why minimizing the use of weight tags for grouping qMRI inputs is important
  • Re-organized suffix justification section w.r.t. thesuffix classes.
  • Added principles for adding a new suffix.
  • Added answers to some plausible questions under suffix section, specifically for MPM & MTS convention.
• Improved main spec

  • Re-structure suffix section in the specification: Created 3 classes

  • Updated tables and explanations wrt 3 classes

  • Added rules for grouping suffix,indexable_metadata and acq-<label>

  • Added new text for elaborating on JSON files accompanying grouping suffixes

    • Added method specific priority levels table to relate grouping suffixes with metadata fields
    • Added another table for qMRI applications that can be derived from an existing grouping suffix by means of adding/modifying metadata priority levels.
• TODO
  • parent & child TO BE CHANGED into high & low level, or some other proper pair
  • Take session-<> into account in the explanation of the higher level JSON for grouping suffix
  • Complete B1DAM suffix.
  • Complete PCTS for indexable_metadata, acq and JSON fields.

[KirstieJane]

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>>>> TO BE DISCUSSED START
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Good practice recommendations:

Parameters that are unchanged across the constituents of a
grouped scan collection MAY repeat in every JSON file belonging to that group.
To avoid such redundancy, all the fixed metadata fields MAY be included only
in the JSON file of the first member of a grouped scan collection, where
constituent images are sorted in ascending alphabetical order. If this convention
is followed, then the remaining JSON files MAY only contain parameters that are
subjected to at least one change across all the member images.

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TO BE DISCUSSED END <<<<

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@Gilles86 and I are reviewing this PR and although we can see the benefits of not having to write out the same metadata over and over, we both agree that this proposal breaks the inheritance principle and ends up being much more complicated to implement 😭

I've deleted it for now....sorry @agahkarakuzu! I hope that's ok 😬