pull out table stripe arrays as base layer primitive; unified 'artifact cache' experiment

src/base/base_entry_point.c

@@ -53,6 +53,9 @@ main_thread_base_entry_point(int arguments_count, char **arguments)
   }
   
   //- rjf: initialize all included layers
+#if defined(ARTIFACT_CACHE_H) && !defined(AC_INIT_MANUAL)
+  ac_init();
+#endif
 #if defined(ASYNC_H) && !defined(ASYNC_INIT_MANUAL)
   async_init(&cmdline);
 #endif
@@ -198,6 +201,9 @@ async_thread_entry_point(void *params)
     {
       async_loop_again = 0;
     }
+#if defined(ARTIFACT_CACHE_H)
+    ac_tick();
+#endif
 #if defined(CONTENT_H)
     c_tick();
 #endif