Assert public key value integrity based on encoding

[paulobmarcos]

Public Keys

The value of the public key must be encoded in only one of the following:
Pem, Jwk, Hex, Base64, Base58, Multibase

Where, depending on the encoding, the corresponding property name should be used to match its value:
Pem - publicKeyPem
Jwk - publicKeyJwk
Base64 - publicKeyBase64
Base58 - publicKeyBase58
Multibase - publicKeyMultibase

This raised question of whether we should verify the integrity of the value based on its encoding before adding it to the document.
When reading a document, an entity might have parsing methods for each encoding and it the value doesn't match, the public key might be considered "invalid".