Add "setSmooth" option to font or font texture

[ZeroZ30o]

https://www.sfml-dev.org/documentation/2.4.2/classsf_1_1Font.php

To achieve "pixel-art" fonts, the texture needs to not be smoothed out -however, by default, it is.

Currently I'm doing:
sf::Texture& texture = const_cast<sf::Texture&>(font.getTexture(size));
texture.setSmooth(false);

But it would be better to have "setSmooth(bool)" on the font or "setSmooth(bool, size)" to only un-smooth a particular size.

[Phanoo]

Seems our needs are closely related ! => https://en.sfml-dev.org/forums/index.php?topic=23017.0

You can do it currently, by recompiling sfml and freetype. But yeah, i'd be a nice feature