refactor file structure

lib/main-window.js

@@ -0,0 +1,29 @@
+const electron = require('electron')
+const app = electron.app
+const BrowserWindow = electron.BrowserWindow
+const path = require('path')
+
+var mainWindow = new BrowserWindow({
+  width: 1080,
+  height: 720,
+  'zoom-factor': 1.0,
+  'web-preferences': {
+    'overlay-scrollbars': true
+  },
+  'standard-window': false
+})
+
+const url = path.resolve(__dirname, '../browser/main/index.html')
+
+mainWindow.loadURL('file://' + url)
+
+mainWindow.webContents.on('new-window', function (e) {
+  e.preventDefault()
+})
+
+app.on('activate', function () {
+  if (mainWindow == null) return null
+  mainWindow.show()
+})
+
+module.exports = mainWindow