go.talks: add 'Go from C to Go' talk
go.talks: add 'Go from C to Go' talk

LGTM=adg
R=adg
CC=golang-codereviews
https://golang.org/cl/92900043

Karthikvb/talks,Karthikvb/talks,Karthikvb/talks,Karthikvb/talks,Karthikvb/talks,Karthikvb/talks