First release. See the module description.
Features -------- The site administer can able to-
1. Enable/Disable the subscription form fields.
2. Make fields required.
3. Enable/Disable form fields placeholder and description.
4. Customize the fields placeholder, description and empty error message.
5. (Optionally) Enable Double Opt-in on the form.
6. (Optionally) Enable and Connect with BriteVerify API for the valid email check.