Do not pass high level `PACK` opcode to
notary parsers. Add opcode amount check.
Delete `PACK` cases in notary parsers.
Signed-off-by: Pavel Karpy <carpawell@nspcc.ru>
Add preparator for notary requests. Is parses
raw notary requests, checks if it should be
handled by Alphabet node. If handling is required,
returns `NotaryEvent` that contains information
about contract scripthash, method name and
arguments of the call.
Signed-off-by: Pavel Karpy <carpawell@nspcc.ru>