Update readme to document permanent deletion and rename old delete method to archive (#228)

Author: thewheat

README.md

@@ -167,19 +167,22 @@ ScrollableUserCollection usersScroll = User.scroll();
 List<User> users = usersScroll.getPage();
 usersScroll = usersScroll.scroll();
 
-// Delete a user by Intercom ID
+// Archive a user by Intercom ID
 User user = User.find("541a144b201ebf2ec5000001");
-User.delete(user.getId());
+User.archive(user.getId());
 
-// Delete a user by user_id
+// Archive a user by user_id
 Map<String, String> params = Maps.newHashMap();
 params.put("user_id", "1");
-User.delete(params);
+User.archive(params);
 
-// Delete a user by email
+// Archive a user by email
 Map<String, String> params = Maps.newHashMap();
 params.put("email", "[email protected]");
-User.delete(params);
+User.archive(params);
+
+// Permanently delete a user by Intercom ID
+User.permanentDelete("541a144b201ebf2ec5000001");
 ```
 
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