directory structure change to work with glide

glide has its own requirements. My previous workaround caused me some
code checkin errors. Need to fix this.

weed/command/compact.go

@@ -0,0 +1,45 @@
+package command
+
+import (
+	"github.com/chrislusf/seaweedfs/weed/glog"
+	"github.com/chrislusf/seaweedfs/weed/storage"
+)
+
+func init() {
+	cmdCompact.Run = runCompact // break init cycle
+}
+
+var cmdCompact = &Command{
+	UsageLine: "compact -dir=/tmp -volumeId=234",
+	Short:     "run weed tool compact on volume file",
+	Long: `Force an compaction to remove deleted files from volume files.
+  The compacted .dat file is stored as .cpd file.
+  The compacted .idx file is stored as .cpx file.
+
+  `,
+}
+
+var (
+	compactVolumePath       = cmdCompact.Flag.String("dir", ".", "data directory to store files")
+	compactVolumeCollection = cmdCompact.Flag.String("collection", "", "volume collection name")
+	compactVolumeId         = cmdCompact.Flag.Int("volumeId", -1, "a volume id. The volume should already exist in the dir.")
+)
+
+func runCompact(cmd *Command, args []string) bool {
+
+	if *compactVolumeId == -1 {
+		return false
+	}
+
+	vid := storage.VolumeId(*compactVolumeId)
+	v, err := storage.NewVolume(*compactVolumePath, *compactVolumeCollection, vid,
+		storage.NeedleMapInMemory, nil, nil)
+	if err != nil {
+		glog.Fatalf("Load Volume [ERROR] %s\n", err)
+	}
+	if err = v.Compact(); err != nil {
+		glog.Fatalf("Compact Volume [ERROR] %s\n", err)
+	}
+
+	return true
+}