Added @link to all public functions there have documentation.

And correct a small 'typo'.

lib/Cake/Utility/Hash.php

@@ -38,6 +38,7 @@ class Hash {
  * @param string|array $path The path being searched for. Either a dot
  *   separated string, or an array of path segments.
  * @return mixed The value fetched from the array, or null.
+ * @link http://book.cakephp.org/2.0/en/core-utility-libraries/hash.html#Hash::get
  */
 	public static function get(array $data, $path) {
 		if (empty($data)) {
@@ -85,6 +86,7 @@ public static function get(array $data, $path) {
  * @param string $path The path to extract.
  * @return array An array of the extracted values. Returns an empty array
  *   if there are no matches.
+ * @link http://book.cakephp.org/2.0/en/core-utility-libraries/hash.html#Hash::extract
  */
 	public static function extract(array $data, $path) {
 		if (empty($path)) {
@@ -220,6 +222,7 @@ protected static function _matches(array $data, $selector) {
  * @param string $path The path to insert at.
  * @param array $values The values to insert.
  * @return array The data with $values inserted.
+ * @link http://book.cakephp.org/2.0/en/core-utility-libraries/hash.html#Hash::insert
  */
 	public static function insert(array $data, $path, $values = null) {
 		$tokens = explode('.', $path);
@@ -288,6 +291,7 @@ protected static function _simpleOp($op, $data, $path, $values = null) {
  * @param array $data The data to operate on
  * @param string $path A path expression to use to remove.
  * @return array The modified array.
+ * @link http://book.cakephp.org/2.0/en/core-utility-libraries/hash.html#Hash::remove
  */
 	public static function remove(array $data, $path) {
 		$tokens = explode('.', $path);
@@ -389,6 +393,7 @@ public static function combine(array $data, $keyPath, $valuePath = null, $groupP
  * @link http://book.cakephp.org/2.0/en/core-utility-libraries/hash.html#Hash::format
  * @see sprintf()
  * @see Hash::extract()
+ * @link http://book.cakephp.org/2.0/en/core-utility-libraries/hash.html#Hash::format
  */
 	public static function format(array $data, array $paths, $format) {
 		$extracted = array();
@@ -466,6 +471,7 @@ public static function contains(array $data, array $needle) {
  * @param string $path The path to check for.
  * @return boolean Existence of path.
  * @see Hash::extract()
+ * @link http://book.cakephp.org/2.0/en/core-utility-libraries/hash.html#Hash::check
  */
 	public static function check(array $data, $path) {
 		$results = self::extract($data, $path);
@@ -556,6 +562,7 @@ public static function flatten(array $data, $separator = '.') {
  * @param array $data Flattened array
  * @param string $separator The delimiter used
  * @return array
+ * @link http://book.cakephp.org/2.0/en/core-utility-libraries/hash.html#Hash::expand
  */
 	public static function expand($data, $separator = '.') {
 		$result = array();
@@ -678,6 +685,7 @@ public static function maxDimensions(array $data) {
  * @param string $path The path to extract for mapping over.
  * @param callable $function The function to call on each extracted value.
  * @return array An array of the modified values.
+ * @link http://book.cakephp.org/2.0/en/core-utility-libraries/hash.html#Hash::map
  */
 	public static function map(array $data, $path, $function) {
 		$values = (array)self::extract($data, $path);
@@ -691,6 +699,7 @@ public static function map(array $data, $path, $function) {
  * @param string $path The path to extract from $data.
  * @param callable $function The function to call on each extracted value.
  * @return mixed The reduced value.
+ * @link http://book.cakephp.org/2.0/en/core-utility-libraries/hash.html#Hash::reduce
  */
 	public static function reduce(array $data, $path, $function) {
 		$values = (array)self::extract($data, $path);
@@ -858,11 +867,12 @@ public static function diff(array $data, $compare) {
 	}
 
 /**
- * Merges the difference between $data and $push onto $data.
+ * Merges the difference between $data and $compare onto $data.
  *
  * @param array $data The data to append onto.
  * @param array $compare The data to compare and append onto.
  * @return array The merged array.
+ * @link http://book.cakephp.org/2.0/en/core-utility-libraries/hash.html#Hash::mergeDiff
  */
 	public static function mergeDiff(array $data, $compare) {
 		if (empty($data) && !empty($compare)) {
@@ -932,6 +942,7 @@ public static function normalize(array $data, $assoc = true) {
  * @param array $options Options are:
  * @return array of results, nested
  * @see Hash::extract()
+ * @link http://book.cakephp.org/2.0/en/core-utility-libraries/hash.html#Hash::nest
  */
 	public static function nest(array $data, $options = array()) {
 		if (!$data) {