client: added twitch prime method to resub event
client: added twitch prime method to resub event

Added a 5th parameter to the resub event as you are able to resub with Twitch Prime as well. The message is: ``DBKynd just subscribed with Twitch Prime. DBKynd subscribed for 9 months in a row!``

Followed the same format as tmijs/tmi.js#180

Getting a lot of parameters on this event now... :(
roberthartung/tmi.js,tmijs/tmi.js,d-4-ni/tmi.js,Schmoopiie/tmi.js