Implement named fonts along unicode schema

[DFOXpro]

the actual schema is set an unicode for every class/icon,

instead we can use a named char and a really shorter css, the best example is with Mozilla's Gaia icon font set: https://github.com/fxos-components/fxos-icons

[jjlauer]

Build scripts currently use fontcustom to turn the svg files into the various font files & stylesheets. If there's a way to accomplish it better, open to PRs.

[DFOXpro]

there is, instead of font-custom I'm using the more active grunt-webfont. Right now I'm already fork this project and the Mozilla's one, I will do a push maybe this week but I'm not using nothing from your vagrant setup, BTW the variables in question that enables this feature is the Unicode private use area and the open font ligatures I already set the Unicode data in this font (Visible via Font Forge)