Add extra explanation to wildcard glossary about base domain

[osirisinferi]

Fixes #660

[alexzorin]

Big agree on this change, thanks.

Would you be interested in rewriting the first sentence as well? I have a lot of trouble myself understanding what it says.

If not, I'm happy to just merge this.

[alexzorin]

These are great - they all come up frequently.

1. Annoyingly, because this is markdown, many of the asterisks are being interpreted as emphasis. Could you please escape each of them as \*?
2. Let's split these explanations into 4 or 5 paragraphs

[osirisinferi]

I'll try to learn Markdown in that case first.

[alexzorin]

If you want a convenient way to see how it will be rendered (without actually starting this project up), the forums also use markdown.

So you can just paste the text there and the forum post preview will faithfully render it, including the magic asterisks.

[osirisinferi]

Also reworded some parts a little bit to make it more clear (I think).

[alexzorin]

Just some small nits and simplifications.

My suggested change of "Hostname"→"Name" might confuse novice readers, I'm not sure. But the idea of a wildcard hostname didn't feel good to me.

[alexzorin]

Thanks a lot, I think this is a huge improvement.

One of the wildcard tooltips has messed up formatting, but since that was already an issue before, let's fix that separately.