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1. Initial state:
   1. Ignite WAL are in consistent state relatively to previous full or incremental snapshot.
   2. Every Ignite node has local ConsistentCut future equals to null (node is WHITE).
   3. Empty collection committingTxs (Set<GridCacheVersion>) that goal is to track COMMITTING+ transactions, that aren't part of IgniteTxManager#activeTx . It's automatically shrinks after transaction committed.
2. Ignite node inites a global snapshot, by starting DistributedProcess (by discovery IO):
   
   1. creates a new ConsistentCutMarker.
   2. prepares a marker message that contains the marker and transmits this message to other nodes.
3. Every nodes starts a local snapshot process after receiving the marker message (whether by discovery, or by communication with transaction message) 
   1. Atomically: creates new ConsistentCut future (node becomes RED), creates committingTxs, starts signing outgoing messages with the ConsistentCutMarker.
   2. Write a snapshot record to WAL with the received ConsistentCutMarker (commits LocalState).
   3. Collect of active transactions - concat of IgniteTxManager#activeTx and committingTxs 
   4. Prepares 2 empty collections - before[sent - received] andafter[excludereceived, but not sent] cut.
4. While global Consistent Cut is running 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 on node that commits first (near node for 2PC, backup or primary for 1PC).
5. For every collected active transaction, node waits for Finish message, to extract the ConsistentCutMarker and fills before, after collections:
   1. if received marker is null or differs from local, then transaction on before side
   2. if received color equals to local, then transaction on after side
6. After all transactions finished:
   1. Writes a finish WAL record with ChannelState (before, after). 
   2. Stops filling committingTxs.
   3. Completes ConsistentCut future, and notifies a node-initiator about finishing local procedure (with DistributedProcess protocol).
7. After all nodes finished ConsistentCut, every node stops signing outgoing transaction messages - ConsistentCut becomes future becomes null (node is WHITE again).

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