Fill in `safemethods` fields in contract config files
with methods that do not change contract storages.
Signed-off-by: Pavel Karpy <carpawell@nspcc.ru>
Sidechain contracts include alphabet contracts for governance
and audit, balance, container, neofsid, netmap, reputation
contracts.
Signed-off-by: Alex Vanin <alexey@nspcc.ru>