Implement Dark theme and toggle

[PatHock]

End goal

Toggle between an app-wide eyeball-laser-blast white background theme and a dark theme, preferably with a completely black background. This toggle could be in the settings view.

Relevant Info/Links

https://flutter.io/cookbook/design/themes/
Themes can be applied to MaterialApp objects.

Your Code

Example code from the link above:

MaterialApp(
  title: title,
  theme: ThemeData(
    brightness: Brightness.dark,
    primaryColor: Colors.lightBlue[800],
    accentColor: Colors.cyan[600],
  ),
);