I have been looking for two days now and still can't find where to change the catagory tree.

It currently looks like this:

Maser cat
|_ sub1
|_ sub2
|_ sub3

I want to change it to something like this

Maser cat
- sub1
- sub2
- sub3

Or even put an image in.

Can anyone tell me where I can do this. I just can't fined it no matter how hard i look