Facet multiple folder docbase improve console feedback

In order to create a facet based on multiple folder, the hippo:docbase property of the facet has to be filled with a comma separated list of uuid.

The hippo console gives a wrong feedback when entering a comma separated list of uuids i.e.

"Not a valid JCR identifier"

As suggested by Ard Scrijvers feedback could be improved:

"in case of testing hippo:docbase that when it seems an invalid docbase, we test whether it happens to be a comma separated list of uuids. "

see
https://groups.google.com/forum/#!topic/hippo-community/HSRmIsQlr2I