Cleaned up relation types

ref #6

src/models/entities/Permission.ts

@@ -22,24 +22,18 @@ export abstract class Permission {
    * The permissions principal
    */
   @ManyToOne(() => Principal, principal => principal.permissions)
-  principal: Principal[]
+  principal: Principal;
 
   /**
    * The target
    */
-  @Column({
-    type: 'simple-enum',
-    enum: PermissionTarget
-  })
+  @Column({ type: 'varchar' })
   @IsNotEmpty()
   target: PermissionTarget;
 
   /**
    * The action type
    */
-  @Column({
-    type: 'simple-enum',
-    enum: PermissionAction
-  })
+  @Column({ type: 'varchar' })
   action: PermissionAction;
 }