cmdutil: expand filename format string by templater (BC)
This is BC because '{}' could be a valid filename before, but I believe good
programmers wouldn't use such catastrophic output filenames. On the other
hand, '\' has to be escaped since it is a directory separator on Windows.
Thanks to Matt Harbison for spotting this weird issue.
This patch also adds cmdutil.rendertemplate(ctx, tmpl, props) as a simpler
way of expanding template against single changeset.
.. bc::
'{' in output filename passed to archive/cat/export is taken as a start
of a template expression.
annotate: do not poorly split lines at CR (
issue5798)
mdiff and lines(text) take only LF as a line separator, but str.splitlines()
breaks our assumption. Use mdiff.splitnewlines() consistently.
It's hard to read \r in tests, so \r is replaced with [CR]. I had to wrap
sed by a shell function to silence check-code warning.