Decouple SuiAddress and PublicKeyBytes

[lxfind]

This is the next step for #318.
Currently we are using SuiAddress and PublicKeyBytes interchangeably. But they are different concept. Most of the time we should only be dealing with SuiAddress, which is a hash of PublicKeyBytes (or a hash of ObjectID when we represent object owners).
There should only be two places where PublicKeyBytes are used:

1. Signer/Signature: public key will be needed for signing and signature checking. And eventually the use of any public key should be hidden inside Signer/Signature so no outside code should even refer to it.
2. Authority name will be defined using PublicKeyBytes. There is no reason to use SuiAddress for Authority name. In the future we could consider supporting different schemas for authority as well but for now we will stick with what we have.

This PR does the following:
Base Types:

1. Created a new type SuiAddress, which is similar to PublicKeyBytes in many ways, but different.
2. Removed Authenticator. We no longer need this.

Authority:

1. AuthorityInfo struct should contain AuthorityName, instead of SuiAddress
2. AuthorityPrivateInfo doesn't need address field.

Client:

1. ClientState now has a separate address field and pub_key field. This is a temporary state. Once we have a version of StableSyncSigner that can expose public key, we will remove the pub_key field.
2. SafeClient's address needs to be PublicKeyBytes, instead of SuiAddress.

All over the code base:
Change the use from PublicKeyBytes to SuiAddress as much as I can (except in Authority config and cases where I need it for signing/validating)

[huitseeker]

This is awesome and greatly speeds up #318, I'm fixing the few nits I have by building on top.
TYSVM!