#1 Duplicate sub-category names are not allowed

[Jeremy Maziarz]

I created a source code category and a documentation category. I then created an xml sub cat for source code. then I tried to create an xml sub cat for documentation. I get an error adding the second xml sub cat.

here is the error message:
------------------------------------------

1 error prohibited this category from being saved

There were problems with the following fields:

* Name has already been taken

I think we should be able to have the following:

src -> html
docs -> html