Add Compound-aware nuxeo-document-tree

A compound-aware nuxeo-document-tree should be contributed from the compound documents addon. This three should differ from the regular nuxeo-document-tree as follows:

• Show non-folderish children for CompoundDocument and CompoundDocumentFolder doctypes (see core-types-contrib.xml)
• Stop parent collapsing behavior when we reach documents with CompoundDocument or CompoundDocumentFolder doctypes. This means if we have nested compounds, this behavior stops with the topmost
• Provide a selection highlight when dealing with documents that are of type CompoundDocument and CompoundDocumentFolder or its decents.

Please see the demo for more details about how it should work: compound-tree-poc-demo.mov
POC code available at: https://github.com/nuxeo/nuxeo-web-ui/compare/SUPINT-1976-poc?expand=1

There is a slight change from the POC which concerns sorting: When listing children of a compound document, other compound documents should come at the bottom, i.e., after all other non-compound children.

Note: if the title of the document is updated, the three should be updated accordingly.

AC: WEBUI-757, WEBUI-758, WEBUI-759