allow customising key symbols

[extrawurst]

#464 showed that we should allow overwriting/customizing the symbols we use to show key codes. this can be added similarly to our general key configuration in keys.rs see get_key_symbol

[josmith42]

I think I'd like to take a stab at this.

Question: in addition to implementing the feature, would you like the PR to also update the key config documentation so users know how to customize the symbols?

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.