Add shorthand support for fallbacks

[rymohr]

"{{name?label}}" # use label if name isn't present

[jeffmohr]

For imports, would we lump this all into the "label" column or have two columns for it?

If we keep as one, we could just default to it being label that they entered unless the {{name?label}} format showed up.

[rymohr]

Templates are just a way to evaluate an entity based on its attributes. They refer to attributes but they aren't attributes themselves. (So in this case name and label would be two separate attribute fields.)