Update to use GridXMLHandler static varaibles
Created by: ehunter-usgs
fixes #2 (closed) depends on https://github.com/usgs/pdl/pull/27
also, updated valueExists logic to accept values instead of references to values.
Maintenance scheduled for Thursday, May 23 from 5 PM to 6 PM ET.
Created by: ehunter-usgs
fixes #2 (closed) depends on https://github.com/usgs/pdl/pull/27
also, updated valueExists logic to accept values instead of references to values.