Changed the OutOfBounds exceptions when getting a property
Changed the OutOfBounds exceptions when getting a property

They aren't variables but keys in the $properties array.
Thus the old error message was misleading.

JeroenDeDauw/phpmd,behance/phpmd,phpmd/phpmd,DanielSiepmann/phpmd,ravage84/phpmd,BernardoSilva/phpmd,postalservice14/phpmd