[MAJOR] last bunch of capture changes for mempool v2

The header captures had lots of pools. They have all been transformed.
diff --git a/include/types/capture.h b/include/types/capture.h
index 49f4d53..e37cc48 100644
--- a/include/types/capture.h
+++ b/include/types/capture.h
@@ -31,7 +31,7 @@
     int namelen;			/* length of the header name, to speed-up lookups */
     int len;				/* capture length, not including terminal zero */
     int index;				/* index in the output array */
-    void *pool;				/* pool of pre-allocated memory area of (len+1) bytes */
+    struct pool_head *pool;		/* pool of pre-allocated memory area of (len+1) bytes */
 };
 
 extern struct pool_head *pool2_capture;