open(
path,opts) ->db,err
Open or create a MNEME database
Opens the database file at path. Creates it if it does not exist (unless
opts.create is false). Options: readonly (open read-only),
create (set to false to fail if file does not exist),
sync ("none" to disable fsync, useful for bulk loading),
encryption (table with key_file path or seed+pubkey for
Ed25519-based encryption at rest).