In this version of the databaseReplicated sequential persistent zk nodes
are used to order DDL queries. Db replicated ddl queries are executed
in the backgrould pool no matter whether it's proposed by the same
replica or not.
add an option to create replicated tables within replicated db without specifying zk path and replica id
add replicated sch pool
disable replication of alter queries for replicated tables in replicated dbs
snapshot prototype. amend of replicated db workflow
add prototype of integration tests for replicated db