Add the ability to customize shortcuts

[nlhnt]

Hello,
cannot find any "about" page or menu to edit my shortcuts - these are starting to annoy me whenever i push "alt + s" i get a new tab.
Also I cannot find the history tab - is this still to be added?

[bbondy]

We don't have history yet, it is tracked here: #444
But I renamed the title here for the ability to customize shortcuts.

[luixxiul]

Closing this in favor of #1089