Include the voice file name as a string for NPC voiced output in websocket JSON

In the websocket JSON, it would be great to output the filename of the voiced NPC line along with the text, and a flag denoting the message as a spoken line. This is useful if a websocket listener would like to do some pre-processing on audio in real time.

Note, I plan to implement this myself -- this bug is for tracking purposes. I'm going to start by changing the knownVoiceLinePtrs HashSet to a Dictionary that contains a k/v of the pointer and filename, then use that to propagate the data down to PollAddon, and then down to... I haven't gotten that far yet :)

Thanks!