MXS-1625 All RouteInfo functionality moved to routeinfo.cc

Provides a clearer separation between what deals with query
classification and what deals with query routing.

Functions have only been moved. No other cleanup has been
done.

server/modules/routing/readwritesplit/rwsplitsession.cc

@@ -13,6 +13,7 @@
 
 #include "rwsplitsession.hh"
 #include "rwsplit_internal.hh"
+#include "routeinfo.hh"
 
 RWBackend::RWBackend(SERVER_REF* ref):
     mxs::Backend(ref),
@@ -98,12 +99,3 @@ uint32_t get_internal_ps_id(RWSplitSession* rses, GWBUF* buffer)
 
     return rval;
 }
-
-RouteInfo::RouteInfo(RWSplitSession* rses, GWBUF* buffer):
-    target(TARGET_UNDEFINED),
-    command(0xff),
-    type(QUERY_TYPE_UNKNOWN),
-    stmt_id(0)
-{
-    target = get_target_type(rses, buffer, &command, &type, &stmt_id);
-}