Revert "Travis: bring back v0.12.1 testing."
Revert "Travis: bring back v0.12.1 testing."

This reverts commit e377f664c45f2f1ade57368e1f78cc8ca36510f9.

I was wrong, the fix is not included.

dchest/tweetnacl-js,dchest/tweetnacl-js,dchest/tweetnacl-js,dchest/tweetnacl-js