Added NULL-check to createInstance to avoid NULL-pointer reference if user/pwd is missing from config.
Removed unnecessary code, added error messages, fixed intendation.
dbshard.h:removed unnecessary code
dbshard.c:removed unnecessary code, cleaned up a bit and made some required changes
readwritesplit.c:removed two unnecessary variable assignments.
Added a parsing function to query classifier that returns an array of database names the query uses.
Added a check if the query targets a sharded database. If so, a hint is added that routes the query to the named server.