Add the Visitor Counter Block.

[pento]

Description

Fixes #1.

This PR is based on this earlier effort: WordPress/gutenberg@4426159

Additionally, it adds the following features:

• Use a monospace font, for that LED counter feel.
• Add a faint background 8 behind each digit, giving the appearance of an unlit LED digit.
• Add an option to change how many digits the counter should be padded to.
• Add screen reader text.

Screenshots

[melchoyce]

What do you think about one of these for the block icon?

https://material.io/tools/icons/?icon=trending_up&style=outline
https://material.io/tools/icons/?icon=add_box&style=outline
https://material.io/tools/icons/?icon=plus_one&style=outline

Also — any chance we can vertically center the numbers within the container?

[pento]

Thank you for the suggestions, @melchoyce!

I used the trending_up icon. The fix for the bottom margin being too large was a little hacky, because line-height is weird.

While I was there, I added faded background digits, in the style of a digital clock. This did mean that I had to place each digit in its own <div>, to fake a monospace style (this is most obvious with the digit 1). This is wildly inaccessible, of course, so I've added screen reader text as an alternative. This seems to work as expected when testing in Voiceover.

I've updated the screenshots in the description to match these changes.

[pento]

It occurred to me that there might be a Digital 7 Monospace font. There is, so I switched to that, and removed the fake monospace styling.

I left the screen reader text, as this is still a better option for screen readers than just the number: it provides context that sighted users gain from the visual styling.

[pento]

I'm not wild about the wording of the Padding Digits help text (or the name, "Padding Digits", for that matter). They feel like they were written by a programmer. 😉

[melchoyce]

Looking good. I'm not totally sure what "padding digits" does — just inflate the size?

[pento]

Yah, it adds (or removes) extra zeros when the counter isn't a large enough number to use the full space.

[melchoyce]

Does this need to be a setting, or can we just pick a random number of 0s?

[pento]

It doesn't need to be a setting, it previously had a default of 8: I added the setting to see what it looked like, I'm fine with removing it, too. 🙂

[melchoyce]

Let's nix it 👍