drop some types in

components/LetterOptions.tsx

@@ -4,12 +4,17 @@ import Collapsible from 'react-collapsible'
 import Input from './Input'
 import TextAreaInput from './TextAreaInput'
 import Select from './Select'
+import { IDocProps } from '../interfaces/IDocProps'
 
 //import './LetterOptions.css';
 
 const EXAMPLE_ADDRESS = 'Max Mustermann\nMusterstr. 73\n12345 Musterstadt'
 
-export default function (props) {
+interface IProps extends IDocProps {
+  onChange: () => void
+}
+
+export default function LetterOptions(props: IProps) {
   const templateTypeOptions = [
     {
       value: 'brief-fam',