image: add import comments.

Change-Id: I2d3a1d002ad43af24cd8b451a2cae4c217482675
Reviewed-on: https://go-review.googlesource.com/1237
Reviewed-by: Andrew Gerrand <adg@golang.org>

bmp/reader.go

@@ -5,7 +5,7 @@
 // Package bmp implements a BMP image decoder and encoder.
 //
 // The BMP specification is at http://www.digicamsoft.com/bmp/bmp.html.
-package bmp
+package bmp // import "golang.org/x/image/bmp"
 
 import (
 	"errors"

cmd/webp-manual-test/main.go

@@ -1,6 +1,6 @@
 // Program webp-manual-test checks that the Go WEBP library's decodings match
 // the C WEBP library's.
-package main
+package main // import "golang.org/x/image/cmd/webp-manual-test"
 
 import (
 	"bytes"

riff/riff.go

@@ -11,7 +11,7 @@
 //
 // A detailed description of the format is at
 // http://www.tactilemedia.com/info/MCI_Control_Info.html
-package riff
+package riff // import "golang.org/x/image/riff"
 
 import (
 	"errors"

tiff/lzw/reader.go

@@ -8,7 +8,7 @@
 //
 // In particular, it implements LZW as used by the TIFF file format, including
 // an "off by one" algorithmic difference when compared to standard LZW.
-package lzw
+package lzw // import "golang.org/x/image/tiff/lzw"
 
 /*
 This file was branched from src/pkg/compress/lzw/reader.go in the

tiff/reader.go

@@ -5,7 +5,7 @@
 // Package tiff implements a TIFF image decoder and encoder.
 //
 // The TIFF specification is at http://partners.adobe.com/public/developer/en/tiff/TIFF6.pdf
-package tiff
+package tiff // import "golang.org/x/image/tiff"
 
 import (
 	"compress/zlib"

vp8/decode.go

@@ -5,7 +5,7 @@
 // Package vp8 implements a decoder for the VP8 lossy image format.
 //
 // The VP8 specification is RFC 6386.
-package vp8
+package vp8 // import "golang.org/x/image/vp8"
 
 // This file implements the top-level decoding algorithm.
 

vp8l/decode.go

@@ -6,7 +6,7 @@
 //
 // The VP8L specification is at:
 // https://developers.google.com/speed/webp/docs/riff_container
-package vp8l
+package vp8l // import "golang.org/x/image/vp8l"
 
 import (
 	"bufio"

webp/decode.go

@@ -6,7 +6,7 @@
 //
 // WEBP is defined at:
 // https://developers.google.com/speed/webp/docs/riff_container
-package webp
+package webp // import "golang.org/x/image/webp"
 
 import (
 	"bytes"

webp/nycbcra/nycbcra.go

@@ -4,7 +4,7 @@
 
 // Package nycbcra provides non-alpha-premultiplied Y'CbCr-with-alpha image and
 // color types.
-package nycbcra
+package nycbcra // import "golang.org/x/image/webp/nycbcra"
 
 import (
 	"image"