all: upgrade to Unicode 11

by running go generate at the top level.

IDNA still uses the old test format. The new
format tests more cases. The 11 format causes
test failure, but only for erroneous input that
result in errors. The package will in all such
cases still report an error, but the value result
may differ.

Updates golang/go#27945

Change-Id: Idb94e78411c2cb9f8e829b09d3d8de7807829076
Reviewed-on: https://go-review.googlesource.com/c/text/+/154442
Run-TryBot: Marcel van Lohuizen <[email protected]>
Reviewed-by: Russ Cox <[email protected]>

Author: mpvl