Merge pull request #574 from JounQin/patch-1

docs: `number` and `null` could be returned by `safeLoad`

Author: Vitaly Puzrin

README.md

@@ -96,7 +96,7 @@ try {
 ### safeLoad (string [ , options ])
 
 **Recommended loading way.** Parses `string` as single YAML document. Returns either a
-plain object, a string or `undefined`, or throws `YAMLException` on error. By default, does
+plain object, a string, a number, `null` or `undefined`, or throws `YAMLException` on error. By default, does
 not support regexps, functions and undefined. This method is safe for untrusted data.
 
 options: