- implement manifest filters to tweak manifests after they have been parsed
- make IEditorValidator public
- stop relying on InternalsVisibleTo Umbraco.ModelsBuilder
* Remove dashboards from Configs().Dashboards
* Remove dashboard.config XML file & associated code reading from XML
* Load Dashboards from TypeLoader into a CollectionBuilder
* Load merge/concat C# Dashboard Types with package.manifest
* Add buildercolletion to an extension method on Composition