Add wins event type to Whiteboard

Labs is amazing. We should celebrate our wins more. This change aims to give people a well-defined venue to tell their peers about their successes, let us all applaud, and give everyone a nice high point to start their day.

Wins is intended to be used "to announce achievements in line with company goals".

It is last in the list of standup items to give everyone a happy point to start their day on. I intend for the tradition to be at least a brief round of applause for each win - though of course, some wins are bigger than others, so people are welcome to celebrate with high fives, cheering, mexican waves.. :)