archive/tar: add Copyright notice to example_test.go

R=golang-dev, mikioh.mikioh
CC=golang-dev
https://codereview.appspot.com/7278050
time: handle zone file with no transitions

Code fix by Alex Bramley.

Fixes issue 4064.

R=golang-dev, adg
CC=golang-dev
https://codereview.appspot.com/7289049
C: add Alex Bramley (Google CLA)

R=golang-dev, bradfitz
CC=golang-dev
https://codereview.appspot.com/7284047