Bump version to 1.2.0 and update version reference in preload.js

Author: vorlie

package.json

@@ -1,6 +1,6 @@
 {
   "name": "iotas-notepad",
-  "version": "1.1.10",
+  "version": "1.2.0",
   "main": "index.js",
   "scripts": {
     "electron": "electron .",

preload.js

@@ -10,6 +10,6 @@ contextBridge.exposeInMainWorld('API', {
     node: () => process.versions.node,
     chrome: () => process.versions.chrome,
     electron: () => process.versions.electron,
-    iotanotepad: () => "1.1.10"
+    iotanotepad: () => "1.2.0"
   },
 });