Snapshot: move old blocks to snapshots (non-async version) (#3309)

cmd/integration/commands/stages.go

cmd/rpcdaemon/cli/config.go

cmd/utils/flags.go

core/rawdb/accessors_chain.go

eth/backend.go

eth/ethconfig/config.go

eth/stagedsync/stage_senders.go

turbo/cli/default_flags.go

turbo/cli/snapshots.go

turbo/snapshotsync/block_snapshots.go

turbo/snapshotsync/block_snapshots_test.go

turbo/snapshotsync/wrapdb.go

turbo/stages/stageloop.go