added a custom defaultLayout, static site, and favicon

Broke hamlet out into standalone files.

I don't like the favicon display; it should be served from /favicon.ico,
but I could only get the static site to serve /static/favicon.ico, so
I had to use a <link rel=icon> to pull it in. I looked at
Yesod.Default.Handlers.getFaviconR, but it doesn't seem to embed
the favicon into the binary?

Utility/Yesod.hs

@@ -0,0 +1,18 @@
+{- Yesod stuff
+ -
+ - Copyright 2012 Joey Hess <joey@kitenet.net>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Utility.Yesod where
+
+import System.FilePath
+
+{- Filename of a template, in the templates/ directory. -}
+template :: FilePath -> FilePath
+template f = "templates" </> f
+
+{- A hamlet template file. -}
+hamletTemplate :: FilePath -> FilePath
+hamletTemplate f = template f ++ ".hamlet"