2016/applicative: add link to YouTube recording

Browsing through the slides today, I did a quick search and found the link
to the recording of Sameer Ajmani's talk at ACM Applicative on June 1, 2016.
This CL updates the "we'll add a link when the video is available" to the
link because, hey, it's available!

Great talk, Sameer.

Change-Id: Ia0bb0c938f8f38e52ef928185a9b2c4adf747853
Reviewed-on: https://go-review.googlesource.com/24866
Reviewed-by: Sameer Ajmani <sameer@golang.org>
1 file changed