[ref] documents+network-documents: create DomainName type

Cargo.lock

lib/modules/ws2p/ws2p-messages/lib.rs

lib/tools/documents/Cargo.toml

lib/tools/documents/src/documents/certification.rs

lib/tools/documents/src/documents/identity.rs

lib/tools/documents/src/documents/membership.rs

lib/tools/documents/src/documents/mod.rs

lib/tools/documents/src/documents/revocation.rs

lib/tools/documents/src/documents/transaction.rs

lib/tools/documents/src/lib.rs

lib/tools/network-documents/Cargo.toml

lib/tools/network-documents/src/host.rs

lib/tools/network-documents/src/lib.rs

lib/tools/network-documents/src/network_documents.pest

lib/tools/network-documents/src/network_endpoint.rs

lib/tools/network-documents/src/network_head_v3.rs

lib/tools/network-documents/src/network_peer.rs