branchmap: fix blank line position The blank line was after was after the `if` condition instead of before.

histedit: add more detailed help about "--outgoing"

histedit: abort if there are multiple roots in "--outgoing" revisions Before this patch, if there are multiple roots in "--outgoing" revisions, result of "histedit --outgoing" depends on the parent of the working directory. It succeeds only when the parent of the working directory is a descendant of the oldest root in "--outgoing" revisions, and fails otherwise. It seems to be ambiguous and difficult for users. This patch makes "histedit --outgoing" abort if there are multiple roots in "--outgoing" revisions always.