Adds support for sendgrid-python v6
Now supports the newest version of sendgrid's api (https://github.com/sendgrid/sendgrid-python/releases/tag/v6.0.0). Maintains backwards compatibility.
Now supports the newest version of sendgrid's api (https://github.com/sendgrid/sendgrid-python/releases/tag/v6.0.0). Maintains backwards compatibility.