Suggestion: Cabal shim added.

I'm new to Haskell, and the very first thing that appears to be necessary with Haskell, is Cabal.

So I think it's a reasonable decision to make a shim for it.

haskell.json

@@ -11,6 +11,7 @@
 		"bin\\hpc.exe",
 		"bin\\hsc2hs.exe",
 		"bin\\runghc.exe",
-		"bin\\runhaskell.exe"
+		"bin\\runhaskell.exe",
+		"lib\\extralibs\\bin\\cabal.exe"
 	]
-}
+}