Add a term to annotate a string parameter that refers to the name of the column in input (fits, csv etc.) file

[dsavchenko]

Particularly useful in Galaxy as there exists a mechanism to generate "select" parameter options from the input dataset (or its metadata).
May require adaptation of the fits datatype, e.g. adding a list of columns to the meta-data

May also be used in MMODA after implementing input fits file reading client-side