Config setting to enable/disable emails

[rakema01]

Would like to see a setting to enable or disable emails for account creation. Email verification is nice for private trackers, but a basic user/pass authentication method is great for semi-private trackers that want to deter its users from spreading the torrents to public forums but don't want to collect and store emails, whether due to privacy or security reasons.

[mickvandijke]

51ba069

Added the option to set email requirement during sign-up to either: Required, Optional or None.

None: