Fix NavigationStuckEvent set-null

If you set the action in a NavigationStuckEvent, it throws an NPE rather
than simply doing nothing. This patches that.
It also throws the event even when the default stuck action is null.
Merge pull request #83 from mcmonkey4eva/master

Fix NavigationStuckEvent set-null
Send tablist packet globally
Merge branch 'master' of github.com:CitizensDev/Citizens2
Merge pull request #12 from CitizensDev/master

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