Modified the link to resend the confirmation instructions on home page. Now when user click on this link, a new confirmation email will be sent to the user.

refs #1413
Merge branch 'master' into Bug1413
Use devise's methods to send confirmation, no need for a new action

Now we override #after_resending_confirmation_instructions_path_for on
devise's confirmation controller and that is enough to make the resend
confirmation instructions work for logged users.
Actually it was already working before, the problem was the redirection and
the error message shown.

refs #1413
Don't let confirmed users to request confirmation instructions

If the user is signed in and is already confirmed, he shouldn't be able
to request confirmation instructions. Just send him back to his home page
with a message.

refs #1413
Merge pull request #59 from mconf/Bug1413

A new method to resend confirmation instructions to the user

refs #1413