Add option to pull images quietly

Add `--quiet` to the `docker image pull` subcommand that will not pull
the image quietly.

```
$ docker pull -q golang
Using default tag: latest
```

Signed-off-by: Vincent Demeester <vincent@sbr.pm>

e2e/image/pull_test.go

@@ -5,6 +5,8 @@ import (
 
 	"github.com/docker/cli/e2e/internal/fixtures"
 	"github.com/docker/cli/internal/test/environment"
+	"gotest.tools/assert"
+	is "gotest.tools/assert/cmp"
 	"gotest.tools/golden"
 	"gotest.tools/icmd"
 	"gotest.tools/skip"
@@ -32,6 +34,13 @@ func TestPullWithContentTrust(t *testing.T) {
 	golden.Assert(t, result.Stdout(), "pull-with-content-trust.golden")
 }
 
+func TestPullQuiet(t *testing.T) {
+	result := icmd.RunCommand("docker", "pull", "--quiet", fixtures.AlpineImage)
+	result.Assert(t, icmd.Success)
+	assert.Check(t, is.Equal(result.Stdout(), "registry:5000/alpine:3.6\n"))
+	assert.Check(t, is.Equal(result.Stderr(), ""))
+}
+
 func TestPullWithContentTrustUsesCacheWhenNotaryUnavailable(t *testing.T) {
 	skip.If(t, environment.RemoteDaemon())
 

e2e/image/testdata/pull-with-content-trust.golden

@@ -2,3 +2,4 @@ Pull (1 of 1): registry:5000/trust-pull:latest@sha256:641b95ddb2ea9dc2af1a0113b6
 sha256:641b95ddb2ea9dc2af1a0113b6b348ebc20872ba615204fbe12148e98fd6f23d: Pulling from trust-pull
 Digest: sha256:641b95ddb2ea9dc2af1a0113b6b348ebc20872ba615204fbe12148e98fd6f23d
 Status: Downloaded newer image for registry:5000/trust-pull@sha256:641b95ddb2ea9dc2af1a0113b6b348ebc20872ba615204fbe12148e98fd6f23d
+registry:5000/trust-pull:latest