[arch-haskell] add haskell-yaml and haskell-svgcairo

[Linus Arver]

Hello,

Could the yaml [1] and svgcairo [2] packages be added to [haskell]? I
don't have a particularly good reason why except that I use both
packages in some of my pet projects.

[1] http://hackage.haskell.org/package/yaml/
[2] http://hackage.haskell.org/package/svgcairo/

Thanks,
Linus