[CryptographyClient] WIP Implementation

[sadasant]

Based on: #4415

If merged,
fixes #4415

Current questions:

• How do we distinguish between doing a service call or encrypting locally?
  • If the key is a string, is that enough to assume we'll use the remote service?
  • Otherwise, should we always try to get the key in order to determine whether we'll do the operation locally or not?
• Does the current KeyVault client has a way of extracting the Key Name and version from the Key's URL?
• Does the current KeyVault client has a way of extracting the version of a Key from the Key's URL?
• If we receive a JWK object as the Key, is there a way to derive the remote key? Should we create a new temporary key?

[sadasant]

Closing in favor of a draft PR

[sadasant]

Here's the draft PR: #4434