client: deprecate NewClientWithOpts in favor of New

Use a more idiomatic name so that it can be used as `client.New()`.

We should look if we want `New()` to have different / updated defaults
i.e., enable `WithEnv` as default, and have an opt-out and have API-
version negotiation enabled by default (with an opt-out option).

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

integration-cli/docker_api_attach_test.go

@@ -177,7 +177,7 @@ func (s *DockerAPISuite) TestPostContainersAttach(c *testing.T) {
 	expectTimeout(wc, br, "stdout")
 
 	// Test the client API
-	apiClient, err := client.NewClientWithOpts(client.FromEnv)
+	apiClient, err := client.New(client.FromEnv)
 	assert.NilError(c, err)
 	defer apiClient.Close()