Implemented the second round of the toResponse normalisationf for all classes

ref #67

src/models/entities/Permission.ts

@@ -6,6 +6,7 @@ import {
 import { Column, Entity, ManyToOne, PrimaryGeneratedColumn } from "typeorm";
 import { PermissionAction } from '../enums/PermissionAction';
 import { PermissionTarget } from '../enums/PermissionTargets';
+import { ResponsePermission } from '../responses/ResponsePermission';
 import { Principal } from './Principal';
 /**
  * Defines the Permission entity.
@@ -51,4 +52,11 @@ export class Permission {
   public toString(): string {
     return this.target + ":" + this.action;
   }
+
+  /**
+   * Turns this entity into it's response class.
+   */
+  public toResponse(): ResponsePermission {
+    return new ResponsePermission(this);
+  }
 }