Use buildah commit and bud in podman

Vendor in buildah and use as much of commit and bug as possible for podman
build and commit.

Resolves #586
Signed-off-by: baude <bbaude@redhat.com>

Closes: #681
Approved by: mheon

vendor/github.com/openshift/imagebuilder/internals.go

@@ -0,0 +1,83 @@
+package imagebuilder
+
+import (
+	"flag"
+	"fmt"
+	"os"
+	"path/filepath"
+	"runtime"
+	"strings"
+	"time"
+)
+
+// hasEnvName returns true if the provided environment contains the named ENV var.
+func hasEnvName(env []string, name string) bool {
+	for _, e := range env {
+		if strings.HasPrefix(e, name+"=") {
+			return true
+		}
+	}
+	return false
+}
+
+// platformSupports is a short-term function to give users a quality error
+// message if a Dockerfile uses a command not supported on the platform.
+func platformSupports(command string) error {
+	if runtime.GOOS != "windows" {
+		return nil
+	}
+	switch command {
+	case "expose", "user", "stopsignal", "arg":
+		return fmt.Errorf("The daemon on this platform does not support the command '%s'", command)
+	}
+	return nil
+}
+
+func handleJSONArgs(args []string, attributes map[string]bool) []string {
+	if len(args) == 0 {
+		return []string{}
+	}
+
+	if attributes != nil && attributes["json"] {
+		return args
+	}
+
+	// literal string command, not an exec array
+	return []string{strings.Join(args, " ")}
+}
+
+// makeAbsolute ensures that the provided path is absolute.
+func makeAbsolute(dest, workingDir string) string {
+	// Twiddle the destination when its a relative path - meaning, make it
+	// relative to the WORKINGDIR
+	if !filepath.IsAbs(dest) {
+		hasSlash := strings.HasSuffix(dest, string(os.PathSeparator)) || strings.HasSuffix(dest, string(os.PathSeparator)+".")
+		dest = filepath.Join(string(os.PathSeparator), filepath.FromSlash(workingDir), dest)
+
+		// Make sure we preserve any trailing slash
+		if hasSlash {
+			dest += string(os.PathSeparator)
+		}
+	}
+	return dest
+}
+
+// parseOptInterval(flag) is the duration of flag.Value, or 0 if
+// empty. An error is reported if the value is given and is not positive.
+func parseOptInterval(f *flag.Flag) (time.Duration, error) {
+	if f == nil {
+		return 0, fmt.Errorf("No flag defined")
+	}
+	s := f.Value.String()
+	if s == "" {
+		return 0, nil
+	}
+	d, err := time.ParseDuration(s)
+	if err != nil {
+		return 0, err
+	}
+	if d <= 0 {
+		return 0, fmt.Errorf("Interval %#v must be positive", f.Name)
+	}
+	return d, nil
+}