docs, fix https://github.com/andgineer/TRegExpr/issues/304

[User4martin]

Further down in the "boundary" part

Meta-char ``.`` (dot) by default matches any character, but if you
turn **off** the `modifier /s <#s>`_, then it won't match line-breaks inside the string.

Also needs to move.

[Alexey-T]

Thanks for note, moved now.

[User4martin]

Better.... The more I look, the more I find.

The meta-classes in the table below have the note

You may use all meta-classes, mentioned in the table above, within
`user character classes <User Character Classes_>`_.

Which does not extend to the "dot", but may be misread.

---

I would

• move the "dot meta" below the "meta classes table"
• Add to the "dot meta"

  The ``.`` does not act as meta class inside `user character classes <User Character Classes_>`_.
  ``[.]`` means a literal "."

[Alexey-T]

'Dot' topic is now separate:

[User4martin]

looks ok to me

[Alexey-T]

@andgineer Pls apply.