the loop-with-small block size. Performance improvements in loading refs are extreme;
segments can be loaded in <1ms. chr1 in its entirety can be loaded in 1.5sec (down
from 30sec).
git-svn-id: file:///humgen/gsa-scr1/gsa-engineering/svn_contents/trunk@1781 348d0f76-0448-11de-a6fe-93d51630548a