Fix builds, revert JavascriptValidator generics removal

Created by: dbluhm

I added org.eclipse.ice.data to the build and discovered there were more issues with JavascriptValidator than I originally thought. I reverted the removal of the generics and fixed my type lookup mechanism to accommodate passing through values to be interpolated by velocity. I'm not particularly fond of that need but I think it's better to just fix the issues and address the bigger issue down the road.