Bug 243430

Currently, an "Add to Watched Nicknames" action is shown in the context menu of nicknames in chat text views, items in channel nickname lists and the empty areas of the chat text views in query tabs.

However, it behaves inconsistently. After someone has been added to the Watched Nicknames Online List, the action gets greyed out in the nickname context menus, but not in the context menu for the empty areas of the chat text views in query tabs.

Further, this design is inconsistent with the similar context menus actions to add someone to the ignore list. Rather than greying out the actions after adding someone, they get replaced with actions to remove someone again. This is better.

Lastly, it would be good if a confirmation message would be shown in the active chat text view after someone has been added or removed from the Watched Nicknames Online list by way of a context menu action.

So, to sum up what must be done:
- All context menus need to show "Add to Watched Nicknames" or "Remove from Watched Nicknames" as applicable.
- Confirmation messages for both actions must be shown in the active chat text view after they have been used.