Populate DistributionZoneManager with CMG listeners to logical topology events

Motivation

In order to calculate dataNodes for each distribution zone it's required to have proper actor that will listen to:

• Logical topology events.
• Distribution zone reconfiguration events (adding, updating, removing).
• Distribution zone processing enabling/disabling.

and properly react to such events.

Given ticket is about logicalTopology events only. On start each DistributionConfiguratoinManager should

• Register logicalTopology onAppeared()/onDisappeared() event handlers that will update logicalToplogy  and topology version in meta storage through invoke. Following condition should be used:

  Conditions.value(logicalTopVersion).eq(event.logicalTopologyVersion - 1)

• Perform initialization
  1. Retrieve logical topology and logical topology version from metastorage.
  2. Retrieve  logical topology and logical topology version from CMG.
  3. Compare aforementioned typologies and versions and if the one in CMG is newer - update it in meta storage through invoke. Following condition should be used: 

     Conditions.value(logicalTopVersion).eq(logical topology version retrieved on step 1)

Definition of Done

• Logical topology and logical topology version are  written to the meta storage as a result of both logical topology events and DistiributionZoneManager initialization.

Implementation Notes

Well, it's pretty straight forward. All logic is described above in Motivation section. Two new keys in meta storage (but not configuration) are expected.