git-svnimport: support for incremental import This adds ability to do import "in chunks" (default 1000 revisions), after each chunk git repo will be repacked. The option -R is used to change default value of chunk size (or how often repository will repacked). Signed-off-by: Sasha Khapyorsky <sashak@voltaire.com> Signed-off-by: Junio C Hamano <junkio@cox.net>