* Remove Roles

* Add AccessControl and tests

* Removed IAccessControl

* Add RoleGranted and RoleRevoked events

* Make roles grantable and revokable regardless of their previous status

* Fix typo

* Add documentation

* Cleanup tests

* Add enumeration tests

* Add _setRoleAdmin tests

* Fix lint error

* Fix AccessControl link in docs

* WIP on access control guide

* Rename getRoleMembersCount

* Add tests for new role admin

* Make AccessControl GSN compatible

* Update access control guide

* Rename admin to adminRole

* Rename roleIds to roles

* Add 'operator' to RoleGranted and RoleRevoked events.

* Only emit events if the roles were not previously granted/revoked

* Uncomment expectEvent.not tests

* Rename operator to sender

* Add changelog entry