Split cmd now processes commits in topo order.

Added the "--topo-order" option to git rev-list.  Without this, it seems that
the revision list is coming back in reverse order but it is sorted
chronologically.  This does not gurantee that parent commits are handled
before child commits.
diff --git a/git-subtree.sh b/git-subtree.sh
index ce94d36..390c0fc 100755
--- a/git-subtree.sh
+++ b/git-subtree.sh
Binary files differ