Fixed (partly) FS#2310 - Template switch not working in mailuser module, for dashlets and the login page

- Added "Generate Password" links to forms of the sites module.

- Fastcgi: delete .php-fcgi-starter directory if another PHP mode is used.

- Added PHP-FPM pm settings (pm.max_children, pm.start_servers, pm.min_spare_servers, pm.max_spare_servers) to the "Options" tab of a website.

- Added SEO redirects (both Apache & nginx) to redirect from non-www website to www website or vice versa.
- Introduced placeholder [scheme] for redirect paths for alias and subdomains; will be replaced with http or https, depending on what the visitor uses.

- Fixed FS#1745.

Merged all language files.

- Added onKeypress handler for the username field in the login form.

- Full merge of all language
- Small italian update