Show asked in main view for restrictions and add Filter by on-demand

Fixes #1281

If a restriction is selected in the main view, questionmarks will indicate whether that restriction will be asked for or not.

Filter by on-demand will show either the apps for which on-demand is enabled, or the apps for which the selected restriction will be asked for, depending on whether a restriction is selected or not.

Negating the filter shows either the apps for which on-demand is not enabled, or the apps for which the selected restriction will not be asked for - which includes the apps for which on-demand is not enabled, though I'm not decided whether it should include them or not.