BOE Style Format by BoeFormater

Replace some of the styles of the texts published in the "Boletín Oficial del Estado" (BOE) with more pleasant ones.

Strictly:
- Expand the margins to make the body of the text narrower, and therefore, more easily readable.
- Replace the default font, one sans serif, with another with more readable serif.
- Expand the font size in general.
- Extend the spacing.

This is intended to create a more comfortable and easy to read text.