remove some themes

I have see the readme on ../account/default1/themes/THEME/
is a good idea the possibility to remove unused themes (without delete directory)

on readme file the instructions say:
rename THEME directoy with "_" and theme will be disable...

It's all perfect!

only thing this function don't work propretly!
i have try and retry, but also renamed as "_THEME" and other similiar way
...on system theme appear normally...

probably it's only a bug to fix...