title: Sign-up and newsletter forms not working in prestashop 1.6
body: <p>I have just installed prestashop for the first time directly from c pannel, and I have noticed 2 problems. The customer sign-up and the newsletter subscription are not working. The sign-up form let me introduce the email but then when I introduce the rest of the details and i click submit, it redirects me to the login page with no error message. I also noticed that even when I submit the sign-up form empty with no details, it stills redirects me to the login page, with no errors such as "you have to introduce the requird fields"... And the problem about newsletter subscription is quite the same, it is redirecting me to the homage with no error message. None of the above do not produce any change in the admin panel. </p>
  
  <p>I looked up the authentication.tpl and the blocknewsletter.tpl and I haven't noticed anything wrong.
  I also changed the theme, but the error persists, so I don't think it is a theme-based problem.</p>
  
  <p>P.S.: The url to the site is: <a href="http://www.flamingos.ro/presta/index.php" rel="nofollow">http://www.flamingos.ro/presta/index.php</a></p>
  
  <p>Thanks, hope someone had the some problem and can give me some advice. </p>