Minor cleanup; added first attempt at TreeTool (disabled by default;) removed unreferenced code from DataTableTool
Changed TreeTool to use a TreeDescriptor.
Copying column filter bug fixes from aws-release branch.

Change-Id: I51628f5130062ecf63af3adfbea27f3666d4733e
Merge branch 'master' into aws-release

Conflicts:
	WeaveServices/src/weave/servlets/DataService.java