Revert "Travis: Force timezone to Pacific to make tests pass, for now."

This reverts commit f23a1b8.

See 0a22a83#comments.

Author: sqs

.travis.yml

@@ -13,7 +13,6 @@ install:
   - go get golang.org/x/tools/cmd/vet
 
 script:
-  - export TZ=US/Pacific # TODO: Fix this.
   - go get -t -v ./...
   - diff -u <(echo -n) <(gofmt -d ./)
   - go tool vet ./