- use category class in category admin and appbrowse
=> fix adding a category which was broken
=> fix deleting a category which was broken
=> fix editing a category which was broken
- fix some code errors and typos (missing $ in front of variable names
and so on)
- fixed a lot of warnings that would have been thrown when error_reporting
is set to show notices (if(isset($variable))) instead of if($variable) for
example)