WHAT

Authorizer improvements described in the Epic.

HOW

Change the authorizer validations imposed by createAcls in the following way:

• Users with access to manage ACLs should not be restricted from creating ACLs with themselves as the named principal
• Improve the error message returned by the authorizer when owners attempt to create ACLs for themselves

In addition make change the #acls and #deleteAcl method so they are aware of the owner rules.  This is done to give the user a complete pictures of the ACLs applied to their instance.

• Change #acls so that it additionally to the rules from Kafka's database, the list includes  'synthesized' AclBinding objects representing the owner rules from the static configuration.. 
• Make a complimentary change to #deleteAcl so that attempts to the AclBinding objects belonging to owners are prevented with a clear error message that conveys the special nature of owner rules.
• A new configuration item will be require so that plugin knows which principals are owners.

ACLs rules for system principals such as the canary should remain hidden.