The age function not compatible minimumAge

[lucascdsilva]

Example:

 v::age($format='d/m/Y')->age(18)->validate('01/01/1996') // is false

the $format argument it's useful for validate the value format.

Example:

v::minimumAge(18, $format='d/m/Y')->validate('01/01/1996') // is true

the $format argument it's useful for format the value.