Englacial, periglacial, supraglacial-- processes or settings-- need clearer label

[smrgeoinfo]

These terms are defined as positions (settings), the labels should be updated to reflect whether they are about positions (settings), e.g. 'englacial setting', and distinguish from processes, e.g. 'englacial processes'

see https://github.com/ESIPFed/sweet/pull/190#discussion_r417743512 and #185