all: update code to satisfy golint

This silences all warnings except those about documentation.

Change-Id: I1d61bf871dcfd6d95b53f66d9e9378f4f648c3a0
Reviewed-on: https://go-review.googlesource.com/20464
Reviewed-by: Dmitri Shuralyov <shurcool@gmail.com>
Reviewed-by: Andrew Gerrand <adg@golang.org>
11 files changed