Bump libcompose and its dependencies

vendor/github.com/docker/engine-api/README.md

@@ -0,0 +1,68 @@
+[![GoDoc](https://godoc.org/github.com/docker/engine-api?status.svg)](https://godoc.org/github.com/docker/engine-api)
+
+# Introduction
+
+Engine-api is a set of Go libraries to implement client and server components compatible with the Docker engine.
+The code was extracted from the [Docker engine](https://github.com/docker/docker) and contributed back as an external library.
+
+## Components
+
+### Client
+
+The client package implements a fully featured http client to interact with the Docker engine. It's modeled after the requirements of the Docker engine CLI, but it can also serve other purposes.
+
+#### Usage
+
+You can use this client package in your applications by creating a new client object. Then use that object to execute operations against the remote server. Follow the example below to see how to list all the containers running in a Docker engine host:
+
+```go
+package main
+
+import (
+	"fmt"
+
+	"github.com/docker/engine-api/client"
+	"github.com/docker/engine-api/types"
+	"golang.org/x/net/context"
+)
+
+func main() {
+	defaultHeaders := map[string]string{"User-Agent": "engine-api-cli-1.0"}
+	cli, err := client.NewClient("unix:///var/run/docker.sock", "v1.22", nil, defaultHeaders)
+	if err != nil {
+		panic(err)
+	}
+
+	options := types.ContainerListOptions{All: true}
+	containers, err := cli.ContainerList(context.Background(), options)
+	if err != nil {
+		panic(err)
+	}
+
+	for _, c := range containers {
+		fmt.Println(c.ID)
+	}
+}
+```
+
+### Types
+
+The types package includes all typed structures that client and server serialize to execute operations.
+
+### Server
+
+The server package includes API endpoints that applications compatible with the Docker engine API can reuse. It also provides useful middlewares and helpers to handle http requests.
+
+This package is still pending to be extracted from the Docker engine.
+
+## Developing
+
+engine-api requires some minimal libraries that you can download running `make deps`.
+
+To run tests, use the command `make test`. We use build tags to isolate functions and structures that are only available for testing.
+
+To validate the sources, use the command `make validate`.
+
+## License
+
+engine-api is licensed under the Apache License, Version 2.0. See [LICENSE](LICENSE) for the full license text.