[BUG] Landscape mode

[6801318d8d]

When in landscape mode, i.e. when the phone is rotated 90 degrees clockwise or anticlockwise, the interface isn't shrunk and you need to scroll to see the play / restart / advance buttons (but scrolling that much would hide the timer)

[nsh07]

I will be working on making the UI adaptive for tablets and other large screen devices (in #115), but a phone screen in landscape is more difficult to optimize for because of the very small vertical space. This app in its current state specifically relies on vertical space to arrange the components on-screen. Maybe I can move the navigation bar to the left in this case to increase vertical space? I will share screenshots when I start working on this.

You can also suggest any changes that you think would help in implementing this feature. Thanks!

[nsh07]

For this issue, I will hide the system bars (navigation bar and status bar) when a user enters landscape mode on a device with a narrow screen (like a phone). Further features will be implemented in #179 and #115.