Documentation on describing datasets specifically

[mih]

A start is made with

• tby-ds1 convention #101

However, there are a bunch of related issues that touch upon aspects of this general topic that are unresolved. I think they needs to be addressed together and a coherent document, rather than being solved one by one. Here is the list (I will close the separate issues now, and instead add TODO markers in here):

• Add BP on annotating non-git "subdatasets" #85
• Define @id for dataset content: File(Version) and Subdataset(Version) #78
• Define @id for a Dataset(Version) #76
• Docs on how to annotate "origin-project" for a dataset #59
• Howto annotate that a property uses a controlled vocabulary #54
• Doc section on the conceptual alignment with "HCLSDatasetDescriptions" #37
• Provide guidelines on "what is a single dataset" i.e. scope of a metadata record #25
• Dedicated instructions for DataLad (metalad) users  #23