Follow system configuration for 12/24 hour time

[thehale]

Binary Clock currently uses exclusively "military time" (aka "24 hour time").

By default, the clock should follow the current system configuration.

Ideally, this will also be a setting so users can choose between the following three settings:

1. Follow System Settings (default)
2. 12-hour time
3. 24-hour time

[thehale]

Requested again in a Google Play review today.