some improvements to your newsletter app

[ghost]

Hey man.

I've made some changes to the newsletter app. I hope i improved this a little bit.

I add:

• option for ignoring anchor if NEWSLETTER_TRACKING_LINKS is true
• option to verify an email adress
• a more german translating

It would be nice if you take a look at and give me some feedback.

greetings, lynadge

[Fantomas42]

Thank you for the pull request.

I will take a look on it asap. It's sound promising !