[cairo] Twin is a family now

[Behdad Esfahbod]

Hi,

I think I'm finally done with twin.

There's a bug somewhere with extent calculations, causing some glyphs to be
chopped.  Have not looked into that.  Any help is appreciated.

* Unhinted waterfall:
http://www.gnome.org/~behdad/cairo/twin/twin-waterfall-unhinted.png

* Hinted waterfall:
http://www.gnome.org/~behdad/cairo/twin/twin-waterfall-hinted.png

Moreover, twin is a full family now.  Since it was so easy, I implemented:

* A full range of weights:
http://www.gnome.org/~behdad/cairo/twin/twin-weight.png

* A full range of stretches:
http://www.gnome.org/~behdad/cairo/twin/twin-stretch.png

* Oblique, monospace, and smallcaps:
http://www.gnome.org/~behdad/cairo/twin/twin-variety.png

And of course you can mix and match.  It all feels like ordering a drink at
the Starbucks now.  You can ask for "@cairo:", or:

  "@cairo:ultra-light extra-expanded monospace smallcaps oblique"

oh, with whipped cream.

Cheers,

behdad