Increase keyboard accessibility

[dovematrix]

Not sure if this code is still maintained but increasing accessibility when using the keyboard would help more people being able to use the component. For instance, instead of using the mouse, being able to use the tab key on the keyboard to tab to the first question, then clicking on enter, or the space bar to open and close the answer, then tab again to move to the next question. Adding tabindex="0" to each question will enable you to tab to them.

[jakerella]

That would be a great improvement! Sadly, I am not really maintaining this, but happy to accept PRs.