Make it possible to use the forks feature even when
reading the list of projects from a file, by creating
a list of known prefixes as we go. Forks have to be
listed after the main project in order to be recognised
as such.
Signed-off-by: Frank Lichtenheld <frank@lichtenheld.de> Acked-by: Petr Baudis <pasky@suse.cz> Signed-off-by: Junio C Hamano <junkio@cox.net>