Deprecated manifest table in favor of using "entityType" as public
metadata. Fixed bugs in EntityCache related to refreshing & reusing entity ids.
Moved EntityCache and related classes to WeaveData project.
WeaveDataSource no longer builds XML hierarchy (TODO: use EntityTree).
Generalized EntityTree and EntityTreeDataDescriptor to use
IEntityTreeNode interface.
Implemented DataSourceTreeNode for top-level multi-datasource
EntityTree.
Implemented EntityHierarchySelector with two-pane view.
Fixed server-side null pointer errors.
No longer hiding hierarchy editor by default in Admin Console.
Added IDataSource.refreshHierarchy().