doc: add testing Name method to go1.8.txt

Change-Id: I6d413f747e6a6c30c5e0e9afdffd5ec18dce7e08
Reviewed-on: https://go-review.googlesource.com/29974Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

doc/go1.8.txt

@@ -22,6 +22,7 @@ crypto/x509: support PSS signatures (CL 24743)
 net/http: make Transport retry non-idempotent requests if no bytes written (CL 27117)
 net: support "option ndots:0" in resolv.conf (CL 24901)
 net: use libresolv rules for ndots range and validation (CL 24901)
+testing: add Name method to *T and *B
 runtime: fix map iterator concurrent map check (CL 23711)
 
 Optimizations: