Todo's for bda.contentproxy 

[ ] add a subscriber to object modified events and reindex Title and Language of
    the ATProxiedContent object if the referenced object changes.

[ ] when calling the proxiedcontent browserview i.e. out of a viewlet directly,
    the plone content providers are not found. The workaround for his is
    to make a template available via the skins path, and inside it call then
    the browserview. this must be fixed to get rid of portal_skins.

[ ] write tests