Log a link to fetch EMDB map when opening a PDB model from cryoEM

[Tom Goddard]

PDB models that have an associated EMDB map list that map in the mmCIF metadata. Would be nice to put a link to the EMDB map in the log to make it easy to get the source data. Could add it to the More Info table, or if more visibility is desired could add it after the PDB title "Structure of xyz neurotransmitter, from EMDB 1234 (more info...)"