Add 'make seeds' to make it easy to add seeds

src/chainparamsseeds.h

@@ -2,7 +2,9 @@
 // Distributed under the GPLv3 software license, see the accompanying
 // file COPYING or https://www.gnu.org/licenses/gpl-3.0.en.html
 // THIS FILE IS AUTOGENERATED, DO NOT MODIFY DIRECTLY
-// Instead, run: ./contrib/seeds/generate-seeds.py contrib/seeds
+// Instead, update contrib/seeds/nodes_main.txt then run
+//    ./contrib/seeds/generate-seeds.py contrib/seeds > src/chainparamsseeds.h
+// OR run: make seeds
 #ifndef HUSH_CHAINPARAMSSEEDS_H
 #define HUSH_CHAINPARAMSSEEDS_H
 // List of fixed seed nodes for the Hush network