Make the BoutiquesBidsSingleSubjectMaker accept BIDS datasets

[prioux]

The BoutiquesBidsSingleSubjectMaker module modifies the interface for a tool that works on BIDS datasets sucha that it will work on a single subject.

Make the module more intelligent in that if the user provides a BIDS datasets (userfile class BidsDataset instead of BidsSubject), it just doesn't do anything to it (bypassing all the current logic).

That way we can integrate tools that work for both entire datasets, and for single subjects.

[MontrealSergiy]

1. For participant level I guess.
2. Is it ok to run with same resources (memory, cpu, ...) as in the original boutique?
3. Probably some level compatibility with other modules expected?
4. Boutiques that use type or name checking should be adjusted? Or perhaps better handle within this module?

[MontrealSergiy]

We rutinely check for input following 'sub-xxxx' pattern, it could be adjusted I guess

[prioux]

To rephrase Sergiy's previous comment:

Consequence of this change: adjust all boutiques descriptors, in all plugins, that use the BoutiquesFileTypeVerifier module. Often, we used that module to impose a restriction that the inputs must be named "sub-X". This will no longer be the case if we work on datasets. The current module can make the check for "sub-X" when the chosen input type is a BidsSubject.