Gets a table containing the quests the player has completed. This function will only return data after QueryQuestsCompleted() has been called and the
QUEST_QUERY_COMPLETE event has fired. The keys in the returned table are the numeric questIds, with a value of true for each set key.
See also Quest functions.
questTbl- A table that will be wiped and filled with the quest data (
completedQuests- A hash table containing a list of the questIds the player has completed. (