Convert DanglingOnly to Filters for docker image prune

This fix convert DanglingOnly in ImagesPruneConfig to Filters,
so that it is possible to maintain API compatibility in the future.

Several integration tests have been added to cover changes.

This fix is related to 28497.

A follow up to this PR will be done once this PR is merged.

Signed-off-by: Yong Tang <yong.tang.github@outlook.com>

command/network/prune.go

@@ -5,7 +5,7 @@ import (
 
 	"golang.org/x/net/context"
 
-	"github.com/docker/docker/api/types"
+	"github.com/docker/docker/api/types/filters"
 	"github.com/docker/docker/cli"
 	"github.com/docker/docker/cli/command"
 	"github.com/spf13/cobra"
@@ -50,7 +50,7 @@ func runPrune(dockerCli *command.DockerCli, opts pruneOptions) (output string, e
 		return
 	}
 
-	report, err := dockerCli.Client().NetworksPrune(context.Background(), types.NetworksPruneConfig{})
+	report, err := dockerCli.Client().NetworksPrune(context.Background(), filters.Args{})
 	if err != nil {
 		return
 	}