Rework Show Quest Command

[WaitingIdly]

changes in this PR:

• rework how QuestCommandShow works to use ClientChatEvent.
• make /bq_client show {quest} send a message in chat sharing the quest.

reasoning:
when a player receives a ClientChatReceivedEvent with the relevant message, QuestCommandShow.sentViaClick = true is set to true. then, when the message is clicked, custom logic is fired and sentViaClick is set to false. due to this, the first click on a shared quest works properly, but the second doesnt - you only receive the message once. additionally, this means that if you share -> manually run /bq_client show {quest} the command will have no effect.

another solution might be to override and create a custom ClickEvent, so when getAction is read it is set to be true:

new ClickEvent(ClickEvent.Action.RUN_COMMAND, "/bq_client show " + questId) {
    @Override
    public Action getAction() {
        QuestCommandShow.sentViaClick = true;
        return super.getAction();
    }
}

[jchung01]

Looks good to me