add --mbox output to patchbomb add option to save generated mails in an mbox file for later processing with formail, instead of sending them directly

hgmerge: various cleanups Details: - put temporary file names into variables - make all temporary file names end with random part - cleanup FileMerge handling - do not use hardlinks in FileMerge change test (breaks on FAT) - try harder to keep file mtime unchanged in case of failed merge