kermit: add stat function for individual records
kermit: add stat function for individual records

This allows us to inspect individual records more deeply, including
finding which other records are used by this one (e.g. which images are
in an article), what links are crosslinked, size stats etc.

endlessm/eos-knowledge-lib,endlessm/eos-knowledge-lib,endlessm/eos-knowledge-lib,endlessm/eos-knowledge-lib