Problems parsing BIDS datasets

[astewartau]

The code makes several assumptions that are not always true about BIDS datasets.

• T2*-weighted series may be single-echo or multi-echo. In the case of a single-echo series, BIDS filepaths use the _T2starw suffix rather than _MEGRE, and they do not have an echo-01 pair in the path. (e.g. sub-1_ses-20190213_run-01_part-mag_T2starw.nii)
• Subjects may each have a different number of sessions; sessions may each have a different number of runs; runs may each have a different number of echoes (and some runs may be single-echo and others multi-echo)
• Session names with dates are not parsed correctly (the GUI seems to assume they increment e.g. ses-1, ses-2 etc., but if session dates were used, these may be ses-20230201 etc.).

[astewartau]

Fixed session name problem in https://github.com/QSMxT/QSMxT-UI/commit/d6e42754a3bd5d39a01345639e3f9abcce84ab55