[TYPO3-core] make the tree collapsable

[Martin Kutschker]

Michael Stucki schrieb:
> 
> Thank you, this works fine now. One problem I have is that the changes are
> not detected by my browser, thus I had to clear the cache first. I hope to
> find a better solution for this...

Don't think so. I switch an existing installation (before this) patch to 
the alpha and it was a complete and utter mess until I cleared my 
browsers' cache.

Masi