fix finalized blocks and more

[branciard]

close #235

• introduce group filtering to support 3 validators setup of 3x3x3 nodes in 1 archipel chain
• 1 chain for 3+3+3 nodes. 2/3 gandpa finality means 1/3 down nodes possible for the HA and orchestrators to work properly. For 3 validators setup ( 9 nodes) 2/3 * 9 = 3 nodes can be down at the same moment. The more you add validators setup the more you can tolerate down nodes. The ponzi HA !
• validator setup is composed of : 1 active and 2 passive as before.
• There is a group id to filter leadership decision and alive check and previous orchestrator logic is the same.
• 1 zip conf for all 3 validators setup A, B,C. ( 4 external sentry, 3+3+3 operators nodes).
• zip format prepared for multi-service support and support 3 differents polkadot sessions keys for each group.