Merge branch 'jk/parse-commit-with-malformed-ident'

The commit object parser has been taught to be a bit more lenient to parse timestamps on the author/committer line with a malformed author/committer ident. * jk/parse-commit-with-malformed-ident: parse_commit(): describe more date-parsing failure modes parse_commit(): handle broken whitespace-only timestamp parse_commit(): parse timestamp from end of line t4212: avoid putting git on left-hand side of pipe