Make field name matching broader

Transformed field names are simpler, and the leading hyphen prevents
this from working.
Grammar fix in comment
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Remove dates that are all zeros
Substitute new field names

Closes #60.
Include alternate name fields

This is only necessary so that we always know that fields will have
alternate names. But it’s important that we not use other names,
because we need stable identifiers, since they’re used within the
script.