fixup rpcserver doc and existing account response

client/rpcserver/handlers.go

@@ -459,6 +459,9 @@ func handlePostBond(s *RPCServer, params *RawParams) *msgjson.ResponsePayload {
 		resErr := &msgjson.Error{Code: msgjson.RPCPostBondError, Message: err.Error()}
 		return createResponse(postBondRoute, nil, resErr)
 	}
+	if res.BondID == "" {
+		return createResponse(postBondRoute, "existing account configured - no bond posted", nil)
+	}
 	return createResponse(postBondRoute, res, nil)
 }
 
@@ -1134,29 +1137,29 @@ Registration is complete after the fee transaction has been confirmed.`,
 		pwArgsShort: `"appPass"`,
 		argsShort:   `"addr" bond assetID (lockTime "cert" maintain)`,
 		cmdSummary: `Post new bond for DEX. An ok response does not mean that the bond is active.
-	Bond is active after the bond transaction has been confirmed and the server notified.`,
+		Bond is active after the bond transaction has been confirmed and the server notified.`,
 		pwArgsLong: `Password Args:
-	appPass (string): The DEX client password.`,
+    appPass (string): The DEX client password.`,
 		argsLong: `Args:
-	addr (string): The DEX address to post bond for for.
-	bond (int): The bond amount (in DCR presently).
-	assetID (int): The asset ID with which to pay the fee.
+    addr (string): The DEX address to post bond for for.
+    bond (int): The bond amount (in DCR presently).
+    assetID (int): The asset ID with which to pay the fee.
     cert (string): Optional. The TLS certificate path. Only applicable when registering.
-	maintain (bool): Optional. Whether to maintain the trading tier established by this bond. Only applicable when registering. (default is true)`,
+    maintain (bool): Optional. Whether to maintain the trading tier established by this bond. Only applicable when registering. (default is true)`,
 		returns: `Returns:
-	{
-	  "bondID" (string): The bond transactions's txid and output index.
-	  "reqConfirms" (int): The number of confirmations required to start trading.
-	}`,
+    {
+      "bondID" (string): The bond transactions's txid and output index.
+      "reqConfirms" (int): The number of confirmations required to start trading.
+    }`,
 	},
 	bondOptionsRoute: {
 		argsShort:  `"addr" targetTier (maxBondedAmt bondAssetID)`,
 		cmdSummary: `Change bond options for a DEX.`,
 		argsLong: `Args:
-	addr (string): The DEX address to post bond for for.
-	targetTier (int): The target trading tier.
-	maxBondedAmt (int): The maximum amount that may be locked in bonds.
-	bondAssetID (int): The asset ID with which to auto-post bonds.`,
+    addr (string): The DEX address to post bond for for.
+    targetTier (int): The target trading tier.
+    maxBondedAmt (int): The maximum amount that may be locked in bonds.
+    bondAssetID (int): The asset ID with which to auto-post bonds.`,
 		returns: `Returns: "ok"`,
 	},
 	exchangesRoute: {