THRIFT-3337 Add testBool method to cross tests

This closes #611
diff --git a/test/hs/TestServer.hs b/test/hs/TestServer.hs
index d991de1..fb80cf8 100755
--- a/test/hs/TestServer.hs
+++ b/test/hs/TestServer.hs
@@ -111,6 +111,10 @@
     System.IO.putStrLn $ "testString(" ++ show s ++ ")"
     return s
 
+  testBool _ x = do
+    System.IO.putStrLn $ "testBool(" ++ show x ++ ")"
+    return x
+
   testByte _ x = do
     System.IO.putStrLn $ "testByte(" ++ show x ++ ")"
     return x