Add the proper electron types

Author: pimterry

package-lock.json

@@ -63,6 +63,7 @@
     "babel-plugin-transform-async-to-generator": "^6.24.1",
     "babel-preset-env": "^1.7.0",
     "babel-preset-react": "^6.24.1",
+    "electron": "^3.0.10",
     "electron-forge": "^5.2.3",
     "electron-prebuilt-compile": "3.0.10",
     "tslint": "^5.1.0",