docs: update the default value of maxHttpBufferSize

Following 734f9d1

Author: darrachequesne

README.md

@@ -227,7 +227,7 @@ to a single process.
       - `upgradeTimeout` (`Number`): how many ms before an uncompleted transport upgrade is cancelled (`10000`)
       - `maxHttpBufferSize` (`Number`): how many bytes or characters a message
         can be, before closing the session (to avoid DoS). Default
-        value is `10E7`.
+        value is `1E6`.
       - `allowRequest` (`Function`): A function that receives a given handshake
         or upgrade request as its first parameter, and can decide whether to
         continue or not. The second argument is a function that needs to be