Added SystemVersion to the homescreen

[Ericvf]

For my own reasons I've decided to add the system version of the Switch to the HBMenu. Not sure if this is desirable for everybody but I wanted to contribute this change.

Ideally this shows the System version string exactly as it is in Settings, however I don't know how to obtain that information.

[fincs]

Is this really necessary? The top area with UI elements is already quite cluttered, and this information can be easily checked in system settings...