+ In '--quilt' mode the patches are named like the originating topgit
+ branch. So usually they end up in subdirectories of the output
+ directory. With option '--flatten' the names are mangled such that
+ they end up directly in the output dir (i.e. slashed are substituted by
+ underscores). With '--numbered' (which implies '--flatten') the patch
+ names get a number as prefix to allow getting the order without
+ consulting the series file, which eases sending out the patches.
+