all: specify vanity import paths

This will prevent godoc.org from serving github.com/golang/text.

Change-Id: I2052560826780dd1dd1a5de87dbef88f02956a9a
Reviewed-on: https://go-review.googlesource.com/16670
Reviewed-by: Marcel van Lohuizen <mpvl@golang.org>
11 files changed