Different keyboard shortcuts to support more keyboard layouts

[carstenw]

I cannot use the keyboard shortcut for next/previous file ctrl+[ and ctrl+] because I have a German keyboard layout.

For the [ key I need the AltGr key. The combination of ctrl and AltGr seems not to work. I tried all possible key combinations, but the shortcut doesn't work.

[OlegGontarenko]

For now we are not planing to implement this feature.