fix errata

appendix/appendix-a-errata.md

@@ -42,6 +42,10 @@
 **p.79, ¶4:** "When an untyped constant is assigned to a variable, as in the first statement below, or
 appears on the right-hand side of a variable declaration with an explicit type, as in the other three statements, ..." has it backwards: the <i>first</i> statement is a declaration; the other three are assignments. (Thanks to Yoshiki Shibata, 2015-11-09. Corrected in the third printing.)
 
+**p.112:** Exercise 4.11 calls for a "CRUD" (create, read, update, delete) tool for GitHub Issues. Since GitHub does not currently allow Issues to be deleted, for "delete", read "close". (Thanks to Yoshiki Shibata, 2016-01-18.)
+
+**p.115:** The anchor element in `gopl.io/ch4/issueshtml`'s template is missing a closing `</a>` tag. (Thanks to Taj Khattra, 2016-01-19.)
+
 **p.132, code display following ¶3:** the final comment should read: `// compile error: can't assign func(int, int) int to func(int) int` (Thanks to Toni Suter, 2015-11-21. Corrected in the third printing.)
 
 **p.166, ¶2:** for "way", read "a way". (Corrected in the third printing.)

ch4/ch4-05.md

@@ -255,7 +255,7 @@ GitHub的Web服務接口 https://developer.github.com/v3/ 包含了更多的特
 
 **練習 4.10：** 脩改issues程序，根據問題的時間進行分類，比如不到一個月的、不到一年的、超過一年。
 
-**練習 4.11：** 編寫一個工具，允許用戶在命令行創建、讀取、更新和刪除GitHub上的issue，當必要的時候自動打開用戶默認的編輯器用於輸入文本信息。
+**練習 4.11：** 編寫一個工具，允許用戶在命令行創建、讀取、更新和关闭GitHub上的issue，當必要的時候自動打開用戶默認的編輯器用於輸入文本信息。
 
 **練習 4.12：** 流行的web漫畵服務xkcd也提供了JSON接口。例如，一個 https://xkcd.com/571/info.0.json 請求將返迴一個很多人喜愛的571編號的詳細描述。下載每個鏈接（隻下載一次）然後創建一個離線索引。編寫一個xkcd工具，使用這些離線索引，打印和命令行輸入的檢索詞相匹配的漫畵的URL。
 

ch4/ch4-06.md

@@ -105,7 +105,7 @@ var issueList = template.Must(template.New("issuelist").Parse(`
 </tr>
 {{range .Items}}
 <tr>
-  <td><a href='{{.HTMLURL}}'>{{.Number}}</td>
+  <td><a href='{{.HTMLURL}}'>{{.Number}}</a></td>
   <td>{{.State}}</td>
   <td><a href='{{.User.HTMLURL}}'>{{.User.Login}}</a></td>
   <td><a href='{{.HTMLURL}}'>{{.Title}}</a></td>