anchor.diff:   - connection_security (string): none, SSL/TLS, STARTTLS
    - authentication_method (string): none, normal, encrypted, kerberos, NTLM, TLS certificate
    - check_timeout (number): check for new messages every X seconds
  - - leave_message (boolean): Leave messages on server until I delete them 
  + - leave_message (boolean): Leave messages on server until I delete them
   
   The state _id_ is assigned by the ESI API at the moment of creation.
   
  
positive.code: - id: Id of the account
  - from (struct): an array of recipient information.
   - email (string): the email address of the recipient. required
   - name (string): the optional display name to use for the recipient 
  - to (array): an array of recipient information.
   - email (string): the email address of the recipient. required
   - name (string): the optional display name to use for the recipient 
  - cc (array): an array of recipient information.
   - email (string): the email address of the recipient. required
   - name (string): the optional display name to use for the recipient 
  - bcc (array): an array of recipient information.
   - email (string): the email address of the recipient. required
   - name (string): the optional display name to use for the recipient 
  - subject (string): the message subject
  - html (string): the full HTML content to be sent
  - text (string): optional full text content to be sent
  - headers (array): optional extra headers to add to the message (most headers are allowed)
   - name (string): name of the header
   - value (string): value of the header 
  - attachments (arrary): an array of attachments information
   - type (string): the content type of the attachment
   - name (string): the name of the attachment
   - content (string): content of the attachment 
  - state(read-only): received, componsing, sending, sent
  - folder: inbox, outbox, draft 
  
  The state _id_ is assigned by the ESI API at the moment of creation.
  
  
negative.code: 
  ### Retrieve a Single Message [GET]
  + Response 200
  
      [Message][]
  
  ### Delete a Message [DELETE]
  + Response 204
  