Replacement of master/slave by primary/secondary:

• The Host Controller model resource has an attribute named master. This attribute must be renamed to primary. See for example the output of the following operation: 

  [domain@localhost:9990 /] /host=master:read-resource(include-runtime=true)
  {
  "outcome" => "success",
  "result" => {
  "directory-grouping" => "by-server",
  "domain-controller" => {"local" => {}},
  "domain-organization" => undefined,
  "host-state" => "running",
  "management-major-version" => 20,
  "management-micro-version" => 0,
  "management-minor-version" => 0,
  "master" => true,

• Fix any affected test