The SendGrid API is returning an error when a message implementing TaggableInterface is sent without any tags.

Error from SendGrid API:

Field: categories
Message: The categories array, when used, must have at least one category.
Help: http://sendgrid.com/docs/API_Reference/Web_API_v3/Mail/errors.html#message.categories

Caused by https://github.com/Stampie/Stampie/blob/master/l

The Readme.md is missing critical information:

• what is mandril, where to find it
• what does this extension allow the user to do
• what is the license of this code
• what magento and php combinations are supported and what combinations are regularly tested

codeclimate-test-reporter is deprecated and includes some out of date dependencies.

There are currently several moderate severity warnings for dev environments by way of the outdated request dependency:

• https://nodesecurity.io/advisories/566
• https://nodesecurity.io/advisories/598