fix spelling

lib/api/monitor.js

@@ -44,7 +44,7 @@ function create(type, query, properties, callback){
         if(properties.name){
             params.body.name = properties.name;
         }
-        if(properties.messsage){
+        if(properties.message){
             params.body.message = properties.message;
         }
         if(typeof properties.options === "object"){
@@ -169,7 +169,7 @@ function update(monitorId, query, properties, callback){
         if(properties.name){
             params.body.name = properties.name;
         }
-        if(properties.messsage){
+        if(properties.message){
             params.body.message = properties.message;
         }
         if(typeof properties.options === "object"){