You can now easily hide games on category basis.
Click on a category to cycle through possible checkbox states.
The "ALL" category can now have 3 different states:
[ ] Not checked = Doesn't display all categories (like before)
[v] Checked = Displays all categories (like before)
[X] Cross = Displays all categories except forbidden categories.
The other categories now have 4 different states:
[ ] Not checked = Games containing this category are not filtered (like before)
[v] Enabled = All games containing this category will be displayed (like before)
[X] Forbidden = All games containing this category will NOT be displayed.
[+] Required = All games NOT containing this category will NOT be displayed.
