text: POST /policyDefs admin/admin
  Content-Type: application/json
  
  {
    "name" : "Policy Def One",
    "description" : "This is the first policy def.",
    "policyImpl" : "org.example.PolicyDefOne",
    "icon" : "one"
  }
  ----
  200
  Content-Type: application/json
  
  {
    "id" : "PolicyDefOne",
    "name" : "Policy Def One",
    "description" : "This is the first policy def.",
    "policyImpl" : "org.example.PolicyDefOne",
    "icon" : "one"
  }
  