undefined method `full_messages` for SimpleCommand::Errors about simple_command

[bguban]

Hi @alexperto, as I can see in the source code of the project, full_messages functionality is implemented but wasn't released to RubyGems. So you can point directly to GitHub in your Gemfile.
I created a PR to be able to use ActiveModel::Validations with this gem #19. I hope it will be merged and we can use all features from ActiveModel module.

[bguban]

Hi @alexperto, my merge request which adds ActiveModel::Validations was merged into master, so now you can use all of its power. But unfortunately, the gem still wasn't released onto https://rubygems.org/gems/simple_command/ . So thumb up on #22 to force the release :)