Importing Resources, Strains, SampleDesigns, and Assays should import to SBH subCollections

[cjmyers]

When importing Resources, Strains, and SampleDesigns, should add the results to subCollections for Resources, Strains, SampleDesigns, and Assays within the Study Collection for the open Study.

[cjmyers]

If the subCollections get created using the Welcome sheet in Excel2SBOL, then this should be sufficient to support this behavior.