Add validation for mail model and change
the workflow in the controller
Improve error messages; send test email only if
the email address is not blank
Singular constant name fits better
Explicit check no needed, validation of the action makes the model already
Send email only after the configuration has been saved
Add mailer class
Add route for test mail request
Set up the mail notifier
Configure the controller, model and view to send email
Sending of email should now work
Sending mail now works
Corrections from lslezak review
Merge pull request #46 from vmoravec/mailsettings-bnc-784360

Mailsettings bnc#784360
- added ajax button for sending of test mail through smtp