Remove the Normal and Monoidal classes and related modules.

Since switching to using the unified class everywhere in our tests, these
modules have now become obsolete.

Author: jorisdral

lsm-tree.cabal

@@ -345,17 +345,12 @@ test-suite lsm-tree-test
   other-modules:
     Database.LSMTree.Class
     Database.LSMTree.Class.Common
-    Database.LSMTree.Class.Monoidal
-    Database.LSMTree.Class.Normal
     Database.LSMTree.Model
     Database.LSMTree.Model.IO
-    Database.LSMTree.Model.IO.Monoidal
-    Database.LSMTree.Model.IO.Normal
     Database.LSMTree.Model.Session
     Database.LSMTree.Model.Table
     Test.Data.Arena
     Test.Database.LSMTree.Class
-    Test.Database.LSMTree.Class.Monoidal
     Test.Database.LSMTree.Generators
     Test.Database.LSMTree.Internal
     Test.Database.LSMTree.Internal.BloomFilter