Fix for bug #418

Increased skygw_query_type_t to 16 bits, and corrected the way how those bit fields are checked.
Added tests for cases where autocommit is disabled and corrected old tests.

server/modules/routing/readwritesplit/test/test_implicit_commit1.sql

@@ -1,5 +1,5 @@
 DROP DATABASE If EXISTS FOO;
-SET autocommit=0;
+SET autocommit=1;
 BEGIN;
 CREATE DATABASE FOO; -- implicit commit
 SELECT (@@server_id) INTO @a;