Delete Alex and happy websites, they should redirect to docs (#228)

(Plan from haskell/alex#215, for example.)

The old websites in addition to being in this repo's history are in
`old-www` branches in both projects' repos. That should be enough
redundancy.

That actual adding of the redirects is done out of band, so this does
the other steps.

Author: Ericson2314

README.md

@@ -35,14 +35,6 @@ main = mkContext >>= \ctx -> hakyllWith configuration $ do
   match "img/*" $ do
     route   idRoute
     compile copyFileCompiler
-    
-  match "happy/**" $ do
-    route   idRoute
-    compile copyFileCompiler
-
-  match "alex/**" $ do
-    route   idRoute
-    compile copyFileCompiler
 
   match "css/*" $ do
     route   idRoute