hightlighting typo

[framatophe]

When writing in markdown, sometimes we have to write some HTML code, especially for the typo. For example :

j'écris quelque chose en makdown – mais j'ai besoin d'un demi quadratin &ndash je peux l'écrire en utf8 directement mais je peux aussi avoir besoin de distinguer le demi-quadratin du quadratin comme ça : —

In ReText (another markdown editor) these html code are highlighted. But it would be better if the Abricotine editor translate them directly : when typing — the corresponding typo appears.

The same demand for highlighning nonbreakable spaces (as it is the case with LibreOffice).

[framatophe]

... see also my comment on the issue #14 (a feature that allows the user to write its own colorised sequences).