Bump to 1.5.1 to fix UPS tracking number's validation

Bump version to 1.5

Bump version to 1.4.0

Fix 1.9 compatiblity

ActiveValidators now supports Twitter urls (both URLs and usernames w…

…ith @

Bump version to 1.2.3

ActiveValidators 1.2.2

Changes
 * Added a password validator (based on regexes)
 * Added the contributor section in the README

Bump version to 1.2.1

ActiveValidator 1.2.0: Added IP, credit card and date validations

ActiveValidators 1.1.0