walker into GATK itself, do some cleanup of output messages, and add some bug fixes.
Command-line arguments in walkers are now feature-complete, but still a bit messy.
git-svn-id: file:///humgen/gsa-scr1/gsa-engineering/svn_contents/trunk@203 348d0f76-0448-11de-a6fe-93d51630548a
(yet) deal elegantly with even simple cases.
git-svn-id: file:///humgen/gsa-scr1/gsa-engineering/svn_contents/trunk@180 348d0f76-0448-11de-a6fe-93d51630548a