CMS Foldertree: Hide all folders except document types, content and images

See screenshot.

Currently, the following folders under "CMS Space" are shown:

/document types
/content
/live_en
/preview_en
/urlmapping
/hst-sample
/images

Of these, only the folders that make sense to the Browse perspective should be shown.
Therefor, I'd suggest to hide all folders, except for "document types", "content" and "images" (and whatever other folder that we have an appropriate set of plugins for).

Ideally, also the top node "CMS Space" is hidden.