Given the name of the visited cache (e.g., test.opendap.or_THREDDS) and
the name of the Postgres database table (e.g., thredds_resoponses), print
the URLs and the stored LMT.
A URLGroup is a set of URLs each with the same number of components where
each corresponding component of all the URLs either matches literally or
is a member of an equivalence class.