backend type in log_line_prefix

When Who What
2020-03-15 10:34:51 Peter Eisentraut (petere) Closed in commitfest 2020-03 with status: Committed
2020-03-15 10:34:51 Peter Eisentraut (petere) Changed committer to petere
2020-03-11 18:54:45 Justin Pryzby (justinpryzby) Added justinpryzby as reviewer
2020-03-10 17:10:56 Julien Rouhaud (rjuju) New status: Waiting on Author
2020-03-06 17:36:53 Julien Rouhaud (rjuju) Added rjuju as reviewer
2020-02-23 06:36:25 Peter Eisentraut (petere) Changed authors to Peter Eisentraut (petere)
2020-02-23 06:36:16 Peter Eisentraut (petere) Attached mail thread c65e5196-4f04-4ead-9353-6088c19615a3@2ndquadrant.com
2020-02-23 06:36:16 Peter Eisentraut (petere) Created patch record