Elaborate on possible values in -mempoolreplacement help line

Author: luke-jr

src/init.cpp

@@ -649,7 +649,7 @@ void SetupServerArgs(ArgsManager& argsman)
                              MAX_OP_RETURN_RELAY),
                    ArgsManager::ALLOW_ANY, OptionsCategory::NODE_RELAY);
     argsman.AddArg("-mempoolfullrbf", strprintf("Accept transaction replace-by-fee without requiring replaceability signaling (default: %u)", (DEFAULT_MEMPOOL_RBF_POLICY == RBFPolicy::Always)), ArgsManager::ALLOW_ANY, OptionsCategory::NODE_RELAY);
-    argsman.AddArg("-mempoolreplacement", strprintf("Enable transaction replacement in the memory pool (\"fee,-optin\" = ignore opt-out flag, default: %u)", "fee,-optin"), ArgsManager::ALLOW_ANY, OptionsCategory::NODE_RELAY);
+    argsman.AddArg("-mempoolreplacement", strprintf("Set to 0 to disable RBF entirely, \"fee,optin\" to honour RBF opt-out signal, or \"fee,-optin\" to always RBF aka full RBF (default: %s)", "fee,-optin"), ArgsManager::ALLOW_ANY, OptionsCategory::NODE_RELAY);
     argsman.AddArg("-permitbaremultisig", strprintf("Relay transactions creating non-P2SH multisig outputs (default: %u)", DEFAULT_PERMIT_BAREMULTISIG), ArgsManager::ALLOW_ANY,
                    OptionsCategory::NODE_RELAY);
     argsman.AddArg("-minrelaytxfee=<amt>", strprintf("Fees (in %s/kvB) smaller than this are considered zero fee for relaying, mining and transaction creation (default: %s)",