When importing `conflicts.md` into the Google repo, our internal tools
complained that it contained conflict markers. Similarly, if you ever
get an actual merge conflict in the file, the working-copy
snapshotting would parse our sample conflict markers here, forcing you
to work around it. Let's avoid that by indenting the conflict
markers. Hopefully readers will understand that the leading space is
not part of the markers.
I feel the original -------/+++++++ pair is slightly confusing because
each half can be a separator by itself. I don't know what character other
than '-'/'+' is preferred, but let's pick '%' (for "mod") per @martinvonz
suggestion.
We used to have documention about how conflicts are implemented, but I
removed that a long time ago when I rewrote the README to target users
rather than VCS hackers. Let's have a doc for the VCS hackers (and
curious users) as well, though.
