Allow multiple level sets, pull out default order into "sequence" file

levels/bottom-up/commit-parents/win

@@ -0,0 +1,10 @@
+COMMITS=$(git cat-file --batch-check='%(objectname) %(objecttype)' --batch-all-objects | grep commit | cut -f1 -d" ")
+
+for COMMIT in $COMMITS; do
+    echo a commit named $COMMIT
+    if [ $(git rev-list $COMMIT | wc -l) -ge 3 ]; then
+        exit 0
+    fi
+done
+
+exit 1