This event will be produced by new epoch handler. All
cleanups should be synchronous because smart contract can't
store inner ring votes forever. Therefore voting should be done
in similar time interval for all inner ring nodes.
Signed-off-by: Alex Vanin <alexey@nspcc.ru>
Cleanup table is a cache for inner ring node to look for netmap
snapshot. It updates access time of bootstrapped nodes and will
be used to send `updateState` txs to clean netmap from unresponsive
nodes.
Signed-off-by: Alex Vanin <alexey@nspcc.ru>