Add button for documentation on how to use in the setup page

[V-ed]

A button (similar to the button in the results page to go back to the homepage) would be used to show a modal explaining how this app works :

• How to setup correctly (even if pretty self explanatory)
• How to go to the next voter
  • Both on mobile and on desktop
• Password refers to the password of the results at the end (Define results password on setup #32)
  • It would be very important to mention that nothing is secured, so don't use any sensible password (it is there simply to prevent kids from accessing the results)
• Results can be clicked to cycle through "states", those of which helps discussions at the end

[V-ed]

How to go to the next voter

This is explained again in the pre-voting page, but would be good to writeup in a documentation modal anyway.

It would be very important to mention that nothing is secured, so don't use any sensible password (it is there simply to prevent kids from accessing the results)

There is also now a warning icon with a popover that mentions this - it would be good however to put it in a documentation modal too, especially for those that may not know you can hover over an icon...

Results can be clicked to cycle through "states", those of which helps discussions at the end

This is also now shown on the result page, where the user can press the "Plus" label to reveal more text which explains this point. I'm not sure if I would put it in the documentation, since it's something that happens at the end only, which creates some noise in a documentation if the user is going to forget it anyway.