[texinfo-pretest] Problematic glyphs in HTML output

[Patrice Dumas]

>     I even think that one should fix the "Glyphs for Examples" like
>     "==>" or "-!-", since there are Unicodes for them, too.
> 
> Indeed, Patrice and I wrote down the mappings for everything we could
> find in the "HTML Cross-references" chapter.

For 'print', it seems that we missed the U+22A3 codepoint, I think it should
be used for cross-refs.

For 'point' U+2605 looks like the TeX symbol but not like the info one.
Should we use it for cross refs?

For 'expansion' I believe we should stick with U+2192, and not use U+21A6,
because it is too far from the info output.

--
Pat