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1. Initial state:
   
   1. No concurrent ConsistentCut process is running.
2. User starts a command for creating new incremental snapshot:
   1. Ignite node inits a DistributedProcess with special message holds new ConsistentCutMarker (goal is to notify every node in a cluster about running incremental snapshot).  
3. Process of creation of incremental snapshot can be started by two events (what will happen earlier):
   1. Receive the ConsistentCutMarker by discovery.
   2. Receive the ConsistentCutMarker by transaction message (Prepare, Finish)
4. On receiving the marker, every node: 
   1. Checks whether ConsistentCut has already started for this marker, skip if it has.
   2. Checks local topVersion  with received in marker. Skip if it is different.
   3. In message thread atomically:
      1. creates new ConsistentCut future
      2. creates committingTx, goal is to track COMMITTING+ transactions, that aren't part of IgniteTxManager#activeTx
      3. starts signing outgoing messages with the ConsistentCutMarker.
   4. In background thread:
      1. Writes a ConsistentCutStartRecord  to WAL with the received ConsistentCutMarker .
      2. Collects active transactions - concat of IgniteTxManager#activeTx and committingTxs .
5. While the DistributedProcess  is alive every node signs output transaction messages:
   1. Prepare messages signed with the ConsistentCutMarker  (to trigger ConsistentCut  on remote node, if not yet).
   2. Finish messages signed with the ConsistentCutMarker  (to trigger...) and transaction ConsistentCutMarker  (to notify nodes which side of cut this transaction belongs to).
   3. Finish messages is signed with transaction ConsistentCutMarker on node that commits first.
6. For every collected active transaction, node waits for Finish message, to extract the ConsistentCutMarker  and prepares before , after  collections:it starts listening tx#finishFuture with callback. When callback is called, it extracts txMarker and:
   
   1. if txMarker
   2. if received marker is null or differs from local, then transaction on Before  sideput into before
   3. if received marker txMarker equals to local, then transaction on After  sideput into after
7. After every collected transaction finished:
   1. Writes a ConsistentCutFinishRecord  into WAL with the collections ( before, after ). 
   2. Stops filling committingTxs .
   3. Completes ConsistentCut  future, and notifies a node-initiator about finishing local procedure (with DistributedProcess  protocol).
8. After all nodes finished ConsistentCut :
   1. every node stops signing outgoing transaction messages
   2. ConsistentCut  future becomes null.
   3. Ignite node now in the initial state again
9. Node initiator checks that every node completes correctly and that topVer wasn't changed since start.
   1. If any node complete exceptionally, or topology changed - complete IS with exception.

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