Add proper zip file check

package.json

@@ -56,9 +56,9 @@
     "dagre": "^0.7.4",
     "electron-store": "^1.3.0",
     "eventemitter2": "^4.1.0",
+    "is-zip-file": "^1.0.2",
     "jquery": "^3.2.1",
     "linkurious": "^1.5.1",
-    "magic-number": "^0.1.6",
     "mustache": "^2.3.0",
     "neo4j-driver": "^1.6.2",
     "prop-types": "^15.6.2",

src/components/Menu/MenuContainer.jsx

@@ -23,6 +23,7 @@ import { withParser } from "stream-json/filters/Pick";
 import { streamArray } from "stream-json/streamers/StreamArray";
 import { chain } from "stream-chain";
 import { connectTo } from "stream-json/Assembler";
+var iszip = require('is-zip-file');
 
 export default class MenuContainer extends Component {
     constructor() {
@@ -168,7 +169,7 @@ export default class MenuContainer extends Component {
             var path = files[index].path;
             var name = files[index].name;
 
-            if (path.endsWith(".zip")) {
+            if (iszip.isZipSync(path)) {
                 await createReadStream(path)
                     .pipe(Parse())
                     .on("entry", function(entry) {