add flag type for iden3 did method, network, network id.
All identifiers created from DID iden3 method will have the same binary part in the first byte of a flag.
The second part of the first byte is an identifier of the blockchain network.
The second byte is a binary representation of a network-specific identifier
add flag type for iden3 did method, network, network id.
All identifiers created from DID iden3 method will have the same binary part in the first byte of a flag. The second part of the first byte is an identifier of the blockchain network. The second byte is a binary representation of a network-specific identifier