(Suspended) Add study/subject/activity information to workbook objs

[iqis]

Per Discord conversation @iqis @wendtke 20190625:

A workbooks generally has three ID dimensions:

• What subject(participant)...
• doing what activity....
• in what study.
  ... and may potentially be more.

This information shall be inferred from folder/name structure. See: #21.
This information is key to downstream analysis.

Issue Suspension:

• Already possible to identify workbooks through read_study(), with mechanism proposed here. is it necessary to repeat on individual workbooks?

[wendtke]

• study name
• participant/subject number
• activity/task name/label (common design: baseline, stressor, recovery; with sub-parts involved sometimes)

** simultaneous data collection on multiple participants common (nested within relationship/family/situation; e.g., parent and child). I am trying to think of a scenario in which a participant would be doing two activities simultaneously. The stages procedure I listed above must be mutually exclusive. The two person/one activity set-up is used more often than one person doing multiple things. Obviously, the most common design is one person with 1+ data stream across procedural tasks (baseline, stressor, recovery).

[iqis]

may depend on #36

[iqis]

I propose a very simple naming scheme: {{id1}}_{{id2}}_{{id3}}_..._{{idn}}.xlsx to treat all identifiers the same. This way the user may use any custom definition relevant to his own study. He may then choose to define the id names later on when ingesting the data, or include in to a control file for the study.

[wendtke]

Yes, agreed.