add basic include-code.lua script

fixtures/inc.sql

@@ -0,0 +1,3 @@
+DROP SCHEMA IF EXISTS maryam CASCADE;
+
+CREATE SCHEMA maryam;

fixtures/include-code.md

@@ -0,0 +1,9 @@
+
+```{.sql include=fixtures/inc.sql ranges=2-$ }
+will be removed by include
+```
+
+```sql
+SELECT * FROM source;
+```
+