Can read GFF and dbSNP files correctly.
Traversal engine now supports keeping moving window of reference ordered data along with the locus iterator.
Tested by walking through a sam file keeping track of the dbSNP positions encountered -- they definitely look right...
git-svn-id: file:///humgen/gsa-scr1/gsa-engineering/svn_contents/trunk@13 348d0f76-0448-11de-a6fe-93d51630548a