Remove build support for old GHC

Author: danpalmer

snap-starter.cabal

@@ -44,9 +44,5 @@ Executable snap-starter
     -- warnings allows quicker workflow.
     ghc-options: -threaded -w
   else
-    if impl(ghc >= 6.12.0)
-      ghc-options: -threaded -Wall -fwarn-tabs -funbox-strict-fields -O2
-                   -fno-warn-orphans -fno-warn-unused-do-bind
-    else
-      ghc-options: -threaded -Wall -fwarn-tabs -funbox-strict-fields -O2
-                   -fno-warn-orphans
+    ghc-options: -threaded -Wall -fwarn-tabs -funbox-strict-fields -O2
+                 -fno-warn-orphans