A new object to control state of syncig added. There are 3
state of sync: p2p, reindex and live. P2P and REINDEX sync
used the same massive dumper of blocks to database, but the have
different triggers -> P2P dumps at least 1000 blocks but all of them
must be considered by node as irreversible, REINDEX unconditionally
dumps packages of 1000 of blocks because a block_log contains only
irreversible blocks. LIVE sync uses llive dumper, and dumps blocks one
by one with calling 'hive.push_block' hive fork manager function.
