set interval to default value from original tracker

trackerlogic.c

@@ -252,7 +252,7 @@ size_t return_peers_for_torrent( ot_torrent *torrent, unsigned int amount, char
   }
   if( peer_count < amount ) amount = peer_count;
 
-  r += sprintf( r, "d8:completei%ie10:incompletei%ie8:intervali600e5:peers%i:", seed_count, peer_count-seed_count, 6*amount );
+  r += sprintf( r, "d8:completei%ie10:incompletei%ie8:intervali1800e5:peers%i:", seed_count, peer_count-seed_count, 6*amount );
   if( amount ) {
     unsigned int pool_offset, pool_index = 0;;
     unsigned int shifted_pc = peer_count;