Improve usability of metadata description process

[dcwalk]

From final debrief at April 18 work sesh:

• it seems like there are ways to automate a bunch of this work?
• autofill with a “we think this is the metadata” (automated), prompt user to verify "does this look right?" (@scruss insight-- most EPA data have great metadata)
• better signal of what has been completed in the list (some indication — @dcwalk: update with the title from the metadata? change font?)
• it seems like you'll still need skills/expertise with tagging! not using researcher-specific terms with a folksonomy,
• a way for categories auto-populating (e.g. dropdowns?) to guide input
• allow year selection, keyboard entry on datepicker!! Those dates a couple years back are tiring to get to