deformatters -o: maybe double newline without end-of-line period should give heading-symbol instead of period

[unhammer]

Headings and list items have different syntax, so apertium-deshtml -o can output a ❡ after them, which the disambiguator can use to e.g. relax rules like "always require a verb in a sentence":

$ echo 'Chase bank</h1>' | apertium-deshtml -o
Chase bank[]❡.[][<\/h1>
]

But for plain text, we often have simple headings like

Chase bank

This organisation has an ambiguous name.

Maybe the -o option could give a ❡ instead of just . before double newlines without final punctuation

[unhammer]

(see also TinoDidriksen/Transfuse#15 , I guess such rules would have to go there when running with transfuse, though we should get the simple h1 case solved first there)