Address improper use of recipients field - fixes spree-contrib/spree_email_to_friend#56
Remove unused parameter hide_recipients

hide_recipients parameter is not used. We simplify gem
functionality by removing it. Related tests are also removed.
Remove html from flash message

Fixes spree-contrib/spree_email_to_friend#55
Merge pull request #57 from chaboo/incorrect_recipients

Address improper use of recipients field.