Migration of jsx files to tsx 2 (#850)

This is to continue the work of migrating all the jsx files into tsx
files.
The MO is basically described here: #848.

About 7 files to go...

src/components/LayerEditorGroup.tsx

@@ -0,0 +1,51 @@
+import React from 'react'
+import Icon from '@mdi/react'
+import {
+  mdiMenuDown,
+  mdiMenuUp
+} from '@mdi/js';
+import {
+    AccordionItem,
+    AccordionItemHeading,
+    AccordionItemButton,
+    AccordionItemPanel,
+} from 'react-accessible-accordion';
+
+
+type LayerEditorGroupProps = {
+  "id"?: string
+  "data-wd-key"?: string
+  title: string
+  isActive: boolean
+  children: React.ReactElement
+  onActiveToggle(...args: unknown[]): unknown
+};
+
+
+export default class LayerEditorGroup extends React.Component<LayerEditorGroupProps> {
+  render() {
+    return <AccordionItem uuid={this.props.id}>
+      <AccordionItemHeading className="maputnik-layer-editor-group"
+        data-wd-key={"layer-editor-group:"+this.props["data-wd-key"]}
+        onClick={_e => this.props.onActiveToggle(!this.props.isActive)}
+      >
+        <AccordionItemButton className="maputnik-layer-editor-group__button">
+          <span style={{flexGrow: 1}}>{this.props.title}</span>
+          <Icon
+            path={mdiMenuUp}
+            size={1}
+            className="maputnik-layer-editor-group__button__icon maputnik-layer-editor-group__button__icon--up"
+          />
+          <Icon
+            path={mdiMenuDown}
+            size={1}
+            className="maputnik-layer-editor-group__button__icon maputnik-layer-editor-group__button__icon--down"
+          />
+        </AccordionItemButton>
+      </AccordionItemHeading>
+      <AccordionItemPanel>
+        {this.props.children}
+      </AccordionItemPanel>
+    </AccordionItem>
+  }
+}