Create creates and stores a Signer in the database.

Find retrieves a Signer from the database using the type and id.

List returns a paginated set of Signers, limited to the provided type.

Path returns the complete path for derived keys.

ErrBadQuorum is returned by Create when the quorum provided is less than 1 or greater than the number of xpubs provided.

ErrBadType is returned when a find operation retrieves a signer that is not the expected type.

ErrBadXPub is returned by Create when the xpub provided isn't valid.

ErrDupeXPub is returned by create when the same xpub appears twice in a single call.

ErrNoXPubs is returned by create when the xpubs slice provided is empty.

Signer is the abstract concept of a signer, which is composed of a set of keys as well as the amount of signatures needed for quorum.