reverse_adoc: Clause levels 4 and 5 for Plateau document

[ronaldtse]

reverse_adoc: Clause levels 4 and 5 for Plateau document

[hmdne]

I see some discrepancies here, in AsciiDoc syntax - I use this document as a guide: https://docs.asciidoctor.org/asciidoc/latest/syntax-quick-reference/

The last markup level of our document is <h4> == =====.

According to the reference, levels can go up to 5, where the last one, ====== corresponds to <h5> (but the reference and AsciiDoctor agree on <h6> of this level's representation - let's ignore that for now).

Your suggestion is to output the following code:

[level=6]
===== 建築物モデル（LOD1）の概要

I think you meant level=5. Which could be represented either as:

====== 建築物モデル（LOD1）の概要

Or as:

[level=5]
===== 建築物モデル（LOD1）の概要

I am creating a patch for the second case.

[ronaldtse]

I think you meant level=5.

Whatever Asciidoctor says would be correct here. Thanks for checking.

In Coradoc, we should remove the need for level=? because that was an arbitrary decision by Asciidoctor to limit the number of = symbols.