Major:

change replication_type to ReplicaPlacement, hopefully cleaner code
works for 9 possible ReplicaPlacement
xyz
x : number of copies on other data centers
y : number of copies on other racks
z : number of copies on current rack
x y z each can be 0,1,2

Minor:
weed server "-mdir" default to "-dir" if empty

go/util/file_util.go

@@ -1,7 +1,7 @@
 package util
 
 import (
-  "code.google.com/p/weed-fs/go/glog"
+	"code.google.com/p/weed-fs/go/glog"
 	"errors"
 	"os"
 )