Created user endpoint tests and documentation

docs/models.md

@@ -67,6 +67,16 @@ public class UserRegister {
 }
 ```
 
+## UserCreator
+```csharp
+public class UserCreator {
+    public string Username { get; set; }
+    public string Email { get; set; }
+    public string Password { get; set; }
+    public virtual List<string> Permissions { get; set; }
+}
+```
+
 ## IPermissionOwner
 ```csharp
 public interface IPermissionOwner;