`tmux`-friendly controls?

[taprs]

Hi Jakob! This thing looks cool, thanks!

I recognize that it might not be a common usecase for alen, but I would routinely use it to browse alignments in an ssh session through tmux on macOS. Taken together, it superseeds most of the control key sequences that seem to be hardcoded in alen 😞 specifically, Ctrl-Shift-arrows do not work and ctrl-J jumps to the next pane...

It would be helpful to me if the key bindings were remappable! Otherwise, an alternative control scheme involving less ctrls and shifts would also work.

Cheers, Nikita