Update groups.js
Update groups.js

I have changed SMTP API and also added X-SMTPAPI. The reason for this is to break up the content for easier searches.
ksigler7/docs,Whatthefoxsays/docs,ksigler7/docs,Whatthefoxsays/docs,Whatthefoxsays/docs,sendgrid/docs,ksigler7/docs,sendgrid/docs,sendgrid/docs