glance重构 update 1

Conflicts:
	Gopkg.lock
	pkg/appsrv/appsrv.go
	pkg/cloudcommon/options.go
	pkg/compute/models/hosts.go
	pkg/compute/models/quotas.go
	pkg/compute/service/service.go
	pkg/mcclient/mcclient.go

pkg/util/streamutils/streamutils.go

@@ -0,0 +1,46 @@
+package streamutils
+
+import (
+	"crypto/md5"
+	"fmt"
+	"io"
+)
+
+type SStreamProperty struct {
+	CheckSum string
+	Size     int64
+}
+
+func StreamPipe(reader io.Reader, writer io.Writer) (*SStreamProperty, error) {
+	sp := SStreamProperty{}
+
+	md5sum := md5.New()
+
+	buf := make([]byte, 4096)
+	for {
+		n, err := reader.Read(buf)
+		if n > 0 {
+			sp.Size += int64(n)
+			md5sum.Write(buf[:n])
+			offset := 0
+			for offset < n {
+				m, err := writer.Write(buf[offset:n])
+				if err != nil {
+					return nil, err
+				}
+				offset += m
+			}
+		} else if n == 0 {
+			break
+		}
+		if err != nil {
+			if err == io.EOF {
+				break
+			}
+			return nil, err
+		}
+	}
+
+	sp.CheckSum = fmt.Sprintf("%x", md5sum.Sum(nil))
+	return &sp, nil
+}