Task-indicator

- Pulling tasks in a GUI window, not terminal.

- Fixed task properties popping up when not expected.
- Focus on the query bar when the search window pops up.

- Fixed menu behavior when using GtkStatusIcon.
- Added icons to the tray menu.
- Use single menu code for both indicator types.
- Updated package description.
- Search dialog now shows active tasks first.
- Search dialog now always shows active tasks, even when not matching the query.
- Single instance mode, helps using system shortcuts.

- Changed sorting order of tasks in the tray menu: now showing
10 recent tasks, not most urgent.
- Can now pull tasks using Gtk status icon.

- Added a tray icon for systems that don't have appindicator.
- Fixed menu items not working.

- Better handling of unknown database contents.