Fix a few typos and add a backport (compat) for hex2bin()
diff --git a/user_guide_src/source/changelog.rst b/user_guide_src/source/changelog.rst
index 0895246..4bb2a3e 100644
--- a/user_guide_src/source/changelog.rst
+++ b/user_guide_src/source/changelog.rst
@@ -530,7 +530,7 @@
- `Multibyte String <http://php.net/mbstring>`_ (limited support).
- `Hash <http://php.net/hash>`_ (``hash_equals()``, ``hash_pbkdf2()``).
- `Password Hashing <http://php.net/password>`_.
- - `Array Functions <http://php.net/book.array>`_ (``array_column()``, ``array_replace()``, ``array_replace_recursive()``).
+ - `Standard Functions ``array_column()``, ``array_replace()``, ``array_replace_recursive()``, ``hexbin()``.
- Removed ``CI_CORE`` boolean constant from *CodeIgniter.php* (no longer Reactor and Core versions).
- Log Library will now try to create the **log_path** directory if it doesn't exist.