Fix inconsistency in hashtags event name and hook documentation

In the stream events documentation the hashtags changed event is named
"hashtags-changed", but the code was using "hashtags-edited". Update
the code to match the documentation.

In the hooks documentation the example was showing "hashtags-edited".
Correct it.

Change-Id: I84fc51b260c9a3d054ce3f23737e3098bd75a021
diff --git a/Documentation/config-hooks.txt b/Documentation/config-hooks.txt
index 07f22f3..96dbff5 100644
--- a/Documentation/config-hooks.txt
+++ b/Documentation/config-hooks.txt
@@ -131,7 +131,7 @@
 or via the REST API.
 
 ====
-  hashtags-edited --change <change id>  --change-owner <change owner> --project <project name> --branch <branch> --editor <editor> --added <hashtag> --removed <hashtag> --hashtag <hashtag>
+  hashtags-changed --change <change id>  --change-owner <change owner> --project <project name> --branch <branch> --editor <editor> --added <hashtag> --removed <hashtag> --hashtag <hashtag>
 ====
 
 The `--added` parameter may be passed multiple times, once for each
diff --git a/gerrit-server/src/main/java/com/google/gerrit/server/events/HashtagsChangedEvent.java b/gerrit-server/src/main/java/com/google/gerrit/server/events/HashtagsChangedEvent.java
index 91c14b1..c6a07b3 100644
--- a/gerrit-server/src/main/java/com/google/gerrit/server/events/HashtagsChangedEvent.java
+++ b/gerrit-server/src/main/java/com/google/gerrit/server/events/HashtagsChangedEvent.java
@@ -22,7 +22,7 @@
 import com.google.gerrit.server.data.ChangeAttribute;
 
 public class HashtagsChangedEvent extends ChangeEvent {
-  public final String type = "hashtags-edited";
+  public final String type = "hashtags-changed";
   public ChangeAttribute change;
   public AccountAttribute editor;
   public String[] added;