A checkbox to indicate no DIC, TA, pH, or pCO2 measurements

[lqjiang]

Should we enable SDIS users to indicate that they do not have measurements of DIC, pH, fCO2 (autonomous), or fCO2 (discrete)? Right now, these variables are listed by default with some prefilled out info.

[lkamb]

The Metadata Editor was originally built to follow the OAP Metadata spreadsheet, which had specific sections for the "Big 5" variables, thus the Metadata Editor has separate panels for those variables.

The fact that those panels have some fields pre-filled is driven by the need to have some consistency between how those variables are presented in the metadata, thus the filled-in and uneditable Full Name field. (reference to #109) If no other fields are filled in, those variables are not added to the metadata XML representation.