Add 'New update available' dialog to the electron version (#299)

* build(tsconfig): Rename root tsconfig.json -> tsconfig.base.json

* feat(auto-update): Add update dialog

When new update available than new message will visible of the top of the screen with 2 buttons 'Update' and 'Close'.
- Update button: Update the application (close and restart)
- Close button: Hide the updatePanel

* fix(auto-update): Add types to the event methods

* style: Add comma after SafeStylePipe import

I forgot add the comma when I rebased the branch

* fix(auto-update): Use electron-is-dev package to detect dev build

I removed the isDev() function from the shared util library because it is electron specific code.

* ci: Change osx_image: xcode8.3

Recommended after the last travis upgrade

* feat(auto-update): Add auto update settings page and save config save on electron platform

* ci: Fix osx image

* ci: Upgrade the electron builder -> 19.6.1

The builder now use the 2 package.json structure and build only
the necessary dependencies.

electron/src/app/app.component.html

@@ -1 +1,7 @@
+<app-update-available
+    [showUpdateAvailable]="showUpdateAvailable$ | async"
+    (updateApp)="updateApp()"
+    (doNotUpdateApp)="doNotUpdateApp()">
+</app-update-available>
+
 <router-outlet></router-outlet>