Electron support

From https://github.com/vector-im/vector-web/pull/2511 but with
just the actual electron changes

electron/src/vectormenu.js

@@ -0,0 +1,184 @@
+/*
+Copyright 2016 OpenMarket Ltd
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+const electron = require('electron');
+
+// Menu template from http://electron.atom.io/docs/api/menu/, edited
+const template = [
+  {
+    label: 'Edit',
+    submenu: [
+      {
+        role: 'undo'
+      },
+      {
+        role: 'redo'
+      },
+      {
+        type: 'separator'
+      },
+      {
+        role: 'cut'
+      },
+      {
+        role: 'copy'
+      },
+      {
+        role: 'paste'
+      },
+      {
+        role: 'pasteandmatchstyle'
+      },
+      {
+        role: 'delete'
+      },
+      {
+        role: 'selectall'
+      }
+    ]
+  },
+  {
+    label: 'View',
+    submenu: [
+      {
+        type: 'separator'
+      },
+      {
+        role: 'resetzoom'
+      },
+      {
+        role: 'zoomin'
+      },
+      {
+        role: 'zoomout'
+      },
+      {
+        type: 'separator'
+      },
+      {
+        role: 'togglefullscreen'
+      },
+      {
+        label: 'Toggle Developer Tools',
+        accelerator: process.platform == 'darwin' ? 'Alt+Command+I' : 'Ctrl+Shift+I',
+        click: function(item, focusedWindow) {
+          if (focusedWindow) focusedWindow.toggleDevTools();
+        }
+      }
+    ]
+  },
+  {
+    role: 'window',
+    submenu: [
+      {
+        role: 'minimize'
+      },
+      {
+        role: 'close'
+      }
+    ]
+  },
+  {
+    role: 'help',
+    submenu: [
+      {
+        label: 'riot.im',
+        click () { electron.shell.openExternal('https://riot.im/') }
+      }
+    ]
+  }
+];
+
+if (process.platform === 'darwin') {
+  const name = electron.app.getName()
+  template.unshift({
+    label: name,
+    submenu: [
+      {
+        role: 'about'
+      },
+      {
+        type: 'separator'
+      },
+      {
+        role: 'services',
+        submenu: []
+      },
+      {
+        type: 'separator'
+      },
+      {
+        role: 'hide'
+      },
+      {
+        role: 'hideothers'
+      },
+      {
+        role: 'unhide'
+      },
+      {
+        type: 'separator'
+      },
+      {
+        role: 'quit'
+      }
+    ]
+  })
+  // Edit menu.
+  template[1].submenu.push(
+    {
+      type: 'separator'
+    },
+    {
+      label: 'Speech',
+      submenu: [
+        {
+          role: 'startspeaking'
+        },
+        {
+          role: 'stopspeaking'
+        }
+      ]
+    }
+  )
+  // Window menu.
+  template[3].submenu = [
+    {
+      label: 'Close',
+      accelerator: 'CmdOrCtrl+W',
+      role: 'close'
+    },
+    {
+      label: 'Minimize',
+      accelerator: 'CmdOrCtrl+M',
+      role: 'minimize'
+    },
+    {
+      label: 'Zoom',
+      role: 'zoom'
+    },
+    {
+      type: 'separator'
+    },
+    {
+      label: 'Bring All to Front',
+      role: 'front'
+    }
+  ]
+};
+
+module.exports = electron.Menu.buildFromTemplate(template)
+