logfmt is the format which is used to format the log output for that namespace.
This patch passes "remote {bookmark|branch}: %s" as the logfmt. Space is not
added after bookmark and branch to make output consistent with other details.
Still this is not the best output. We may need to wrap getlogcolumns() to change
spacing in the in built columns to match the remotenames one.
lognames are also deleted as they are superseded by logfmt.