fix date to nil before validation in case of blank components
Version bump to 0.2.2
Merge branch 'master' of https://github.com/masciugo/edtf-rails

* 'master' of https://github.com/masciugo/edtf-rails:
  Regenerate gemspec for version 0.2.2
  Version bump to 0.2.2
  fix date to nil before validation in case of blank components
Regenerate gemspec for version 0.2.2