Feature request

Enable data operations over an array as part of the model server-side with a custom operator

For example, I am planning to use a filter component to a model like this.

public class Person{

    public string Name{get;set;}

    public List<Address> Addresses {get;set;}

}

public class Address{

    public string City{get;set;}

}

Bug report

The Messages option of the Telerik UI Filter is missing the options for:

• AddExpression
• AddGroup
• Close

Reproduction of the problem

1. Create a Filter widget.

2. Try to localize the messages from the above.

3. The options are missing

### Environment

* **Kendo UI version:** 2021.1.330
* **jQuery version:** 1.12.4
* **Browser:** [all]

Hello,

I would like to request the functionality to use server-side editor templates for set fields in the Kendo UI Filter. 

Thank you