Lkt fix

Fix a little lkt and add supports for new functionalities of lektord.

inc/lektor/macro.h

@@ -28,6 +28,9 @@
         goto error;                                                     \
     }
 
+#define SQLITE_DO_ROLLBACK(db)                                          \
+    sqlite3_exec(db, "ROLLBACK TRANSACTION;\n", NULL, NULL, NULL);
+
 #ifndef MAX
 #define MAX(a, b) ((a) < (b) ? (b) : (a))
 #endif /* MAX */