lua: move to lang/ directory

Support for more languages is comming, so let's group them
in a separate directory.

CMakeLists.txt

@@ -508,7 +508,7 @@ set(scylla_sources
     locator/simple_strategy.cc
     locator/snitch_base.cc
     locator/token_metadata.cc
-    lua.cc
+    lang/lua.cc
     main.cc
     memtable.cc
     message/messaging_service.cc

configure.py

@@ -1006,7 +1006,7 @@ scylla_core = (['database.cc',
                 'mutation_writer/shard_based_splitting_writer.cc',
                 'mutation_writer/partition_based_splitting_writer.cc',
                 'mutation_writer/feed_writers.cc',
-                'lua.cc',
+                'lang/lua.cc',
                 'service/raft/schema_raft_state_machine.cc',
                 'service/raft/raft_sys_table_storage.cc',
                 'serializer.cc',

cql3/functions/user_function.cc

@@ -20,7 +20,6 @@
  */
 
 #include "user_function.hh"
-#include "lua.hh"
 #include "log.hh"
 #include "cql_serialization_format.hh"
 

cql3/functions/user_function.hh

@@ -25,7 +25,7 @@
 
 #include "abstract_function.hh"
 #include "scalar_function.hh"
-#include "lua.hh"
+#include "lang/lua.hh"
 
 namespace cql3 {
 namespace functions {

cql3/statements/create_function_statement.cc

@@ -25,7 +25,7 @@
 #include "prepared_statement.hh"
 #include "service/migration_manager.hh"
 #include "service/storage_proxy.hh"
-#include "lua.hh"
+#include "lang/lua.hh"
 #include "database.hh"
 #include "cql3/query_processor.hh"
 

db/schema_tables.cc

@@ -90,7 +90,7 @@
 #include "user_types_metadata.hh"
 
 #include "index/target_parser.hh"
-#include "lua.hh"
+#include "lang/lua.hh"
 
 #include "db/query_context.hh"
 #include "serializer.hh"