command.js allow id with spaces

src/jio/commands/command.js

@@ -157,13 +157,13 @@ var command = function (spec, my) {
    * @param  {object} storage The storage.
    */
   that.validate = function (storage) {
-    if (typeof priv.doc._id === "string" && priv.doc._id.match(" ")) {
+    if (typeof priv.doc._id === "string" && priv.doc._id === "") {
       that.error({
         "status": 21,
         "statusText": "Invalid Document Id",
         "error": "invalid_document_id",
         "message": "The document id is invalid",
-        "reason": "The document id contains spaces"
+        "reason": "empty"
       });
       return false;
     }