Store mapping of wallet connection and email address

Create new HTTP endpoint to accept information about user wallet connection id and email address.

The endpoint will receive a request from the OCM agent when a user authenticates with VC.

The service must store the connectionID and email address, so that later when an email has to be delivered to this email address, the svdx will give the email to the OCM agent for didcomm delivery over the existing connection.

Example request, still to be defined with @zdravko.iliev

POST /v1/ocm/connection

{
  "connection_id": "...",
  "email": "example@vereign.com"
}