ISSUE-157: Updated README.md

Author: raymondschouten

README.md

@@ -15,6 +15,7 @@ Learn more about it in its [documentation](https://github.com/darkwebdesign/symf
 
 ## Features
 
+* ArrayType, handles unstructured array data.
 * BirthdayType, handles birthday data.
 * BooleanType, transforms an user selected value into a boolean.
 * EntityType, transforms an user entered identifier into a Doctrine entity.