fix revisionstorage error, it was writing doc._rev in sub_storage

src/jio.storage/revisionstorage.js

@@ -474,6 +474,7 @@ jIO.addStorageType('revision', function (spec, my) {
     f.postDocument = function (doctree_update_method) {
       revs_info = priv.postToDocumentTree(doctree, doc);
       doc._id = docid + "." + revs_info[0].rev;
+      delete doc._rev;
       that.addJob(
         "post",
         priv.substorage,

test/jiotests.js

@@ -1198,6 +1198,7 @@ test ("Post", function(){
 
     // check document
     o.doc["_id"] = "post1."+o.rev;
+    delete o.doc._rev;
     deepEqual(
         localstorage.getItem(o.localpath + "/post1." + o.rev),
         o.doc,
@@ -1289,6 +1290,7 @@ test ("Put", function(){
 
     // check document
     o.doc._id = "put1." + o.rev;
+    delete o.doc._rev;
     deepEqual(
         localstorage.getItem(o.localpath + "/put1." + o.rev),
         o.doc,