Extend routing documentation

[sis0k0]

Here are a few suggestions for extending the routing section of the docs:

• Tabs navigation;
• Drawer navigation (f.e. document the approach used in the Drawer Navigation template;
• App/Playground sample for navigation when using multiple frames;
• Playground samples (f.e. @jlooper's great samples with dynamic components, $navigateTo and the nativescript-vue-navigator plugin);
• Document the usage of nativescript-vue-navigator.

Please add your use cases and other suggestions for the routing docs in the comments below :)