Player data to Database (#5475)

* Player data to Database

Add player data into databases (SQLite3 & PG only)

PostgreSQL & SQLite: better POO Design for databases

Add --migrate-players argument to server + deprecation warning

* Remove players directory if empty

src/script/lua_api/l_server.h

@@ -92,6 +92,9 @@ class ModApiServer : public ModApiBase
 	// kick_player(name, [message]) -> success
 	static int l_kick_player(lua_State *L);
 
+	// remove_player(name)
+	static int l_remove_player(lua_State *L);
+
 	// notify_authentication_modified(name)
 	static int l_notify_authentication_modified(lua_State *L);