Partial metadata changes

[danielfang97]

"Bulk collection update is possible in SynBioHub but this is possible only by uploading new, full descriptions, not partial metadata changes (like, e.g. changing status to “tested” for selected entities)"
Allow the ability to do bulk collection update of partial metadata. I'm not exactly sure of the need for this change at the current moment. The use case for this is fairly small. This would probably require restructuring of how the data is stored as well as the metadata and JSON pages, so will be put in milestone 3.0 for now.