#15 fix Blank validator test
#15 added remaining validators
#15 typos
#15 added UT for constraint validator factory
#15 typos
#15 test the wrong choices object length
#15 fixed an error causing a valid date string to be flagged as violation
#15 forgot to pass the options object to the parent constructor
#15 removed ip v6 validation for now
#15 fixed test to check if value instance of a constructor
#15 simplified the url regular expression
#15 added constraint validator UT