BIM360 Docs now has the ability to manage Document Sets. When you upload a document pay close attention in the dialog box there is an option to specify a set. This is where you will define what set the document is associated with. Addes with this release is a column named sets in which this metadata is posted to. You can sort and filter by sets which is really a nice way of looking at your plans. Read the full release notes here.
This is considered the first release of this feature so more functionality to come.