Highly tailored filter that outputs well-formed HTML. Be aware that you cannot add any character as you
want. You can filter this stream, but keep it available because it controls the tags.
Because there are so many attributes for each tag, we did not want features with scores
of parameters.%
So, we decided to have a general-purpose with_attribute feature to be called
before a tag creation.
Typical use:
html_out.with_attribute(once "width", once "80%)
html_out.with_attribute(once "align", once "center")
html_out.with_attribute(once "valign", once "top")
html_out.open_table_cell
d