Remove local seqNo

* It does not provide the safetey that was intended
* The seqNo must be used as in the ReplicatedShoppingCartSpec example,
  i.e. get-modify-update cycle with stashing in-between, and that is too
  complicated and too easy to get wrong
* Disabled RemovedNodePruning for now
Merge pull request #18 from patriknw/wip-16-seqNo-patriknw

Remove local seqNo