Remove redux from example package

Removes the redux integration from the example package
and reimplements most of the Redux based custom
functionality with the React standalone variant.

Author: TheZoker

package-lock.json

@@ -7,10 +7,10 @@
     "@jsonforms/examples": "^3.0.0-alpha.2",
     "@jsonforms/react": "^3.0.0-alpha.2",
     "@mui/material": "^5.2.2",
+    "json-refs": "3.0.15",
     "lodash": "^4.17.15",
-    "react": "^17.0.2",
     "react-dom": "^17.0.2",
-    "redux": "^4.0.4"
+    "react": "^17.0.2"
   },
   "scripts": {
     "build": "echo 'Nothing to do'",

packages/example/package.json

@@ -1,5 +1,7 @@
-.App {
-  text-align: center;
+body {
+  margin: 0;
+  padding: 0;
+  font-family: sans-serif;
 }
 
 .App-logo {
@@ -9,15 +11,37 @@
 
 .App-header {
   background-color: #222;
-  height: 150px;
   padding: 20px;
   color: white;
+  text-align: center;
 }
 
 .App-title {
   font-size: 1.5em;
 }
 
+.buttons {
+  margin-bottom: 20px;
+}
+
+button {
+  margin-right: 10px;
+  background-color: #0069ed;
+  color: #ffffff;
+  border: 1px solid;
+  font-size: 1rem;
+  line-height: 1;
+  padding: 0.5rem 1rem;
+  border-radius: 5px;
+  cursor: pointer;
+}
+button:hover {
+  background-color: #0053ba;
+}
+button:active {
+  transform: scale(0.99);
+}
+
 .App-intro {
   font-size: large;
 }
@@ -27,9 +51,18 @@
   to { transform: rotate(360deg); }
 }
 
+pre {
+  overflow-x: auto;
+  background: #ccc;
+  padding: 15px;
+}
+
+.content {
+  padding: 20px;
+}
+
 .data-title {
   text-align: center;
-  margin-bottom: 0;
 }
 
 .data-content {