Tasks operations

All filter:
- add
- edit
- delete
- mark completed
- mark all completed
- make active again
- make all active again
- clear


Active filter:
- create
- edit
- delete
- mark completed
- mark all completed


Completed filter:
- delete
- clear
- make active again
- make all active again


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Switching from filter to filter

All filters:
- switch on Active filter
- switch on Completed filter


Active filter:
- switch on Completed filter
- switch on All filter


Completed filter:
- switch on Active filter
- switch on All filter