Fix inconsistency between definition of request and text

Closes marijnh#511

Author: marijnh

11_async.md

@@ -525,13 +525,13 @@ recursive function—a regular loop doesn't allow us to stop and wait
 for an asynchronous action. The `attempt` function makes a single
 attempt to send a request. It also sets a timeout that, if no response
 has come back after 250 milliseconds, either starts the next attempt
-or, if this was the fourth attempt, rejects the promise with an
+or, if this was the third attempt, rejects the promise with an
 instance of `Timeout` as the reason.
 
 {{index idempotence}}
 
 Retrying every quarter-second and giving up when no response has come
-in after a second is definitely somewhat arbitrary. It is even
+in after three-quarter second is definitely somewhat arbitrary. It is even
 possible, if the request did come through but the handler is just
 taking a bit longer, for requests to be delivered multiple times.
 We'll write our handlers with that problem in mind—duplicate messages

html/errata.html

@@ -58,6 +58,13 @@ <h2>Chapter 10</h2>
 needs it own private scope“, it should say “<em>its</em> own private
 scope“.</p>
 
+<h2>Chapter 11</h2>
+
+<p><strong>Page 189/190</strong> <em>Networks are Hard</em>: The text
+under the code that defines <code>request</code> claims the function
+will give up after four attempts and a second. In fact, it gives up
+after three attempts, in three-quarter second.</p>
+
 <h2>Chapter 14</h2>
 
 <p><strong>Page 234</strong> (2nd) <em>Creating Nodes</em>: In the