distinguish between seeds and manual peers in the config/flags

- we only use seeds if we can’t connect to peers in the addrbook.
- we always connect to nodes given in config/flags

Refs #864

docs/specification/configuration.rst

@@ -49,6 +49,8 @@ The main config parameters are defined
 -  ``p2p.pex``: Enable Peer-Exchange (dev feature). *Default*: ``false``
 -  ``p2p.seeds``: Comma delimited host:port seed nodes. *Default*:
    ``""``
+-  ``p2p.manual_peers``: Comma delimited host:port manual peers. *Default*:
+   ``""``
 -  ``p2p.skip_upnp``: Skip UPNP detection. *Default*: ``false``
 
 -  ``rpc.grpc_laddr``: GRPC listen address (BroadcastTx only). Port

docs/specification/rpc.rst

@@ -111,7 +111,7 @@ An HTTP Get request to the root RPC endpoint (e.g.
     http://localhost:46657/broadcast_tx_commit?tx=_
     http://localhost:46657/broadcast_tx_sync?tx=_
     http://localhost:46657/commit?height=_
-    http://localhost:46657/dial_seeds?seeds=_
+    http://localhost:46657/dial_manual_peers?manual_peers=_
     http://localhost:46657/subscribe?event=_
     http://localhost:46657/tx?hash=_&prove=_
     http://localhost:46657/unsafe_start_cpu_profiler?filename=_