Configure Jenkins with SMTP capability via Send Grid

[rtyler]

It would be very useful to allow Jenkins to send emails via the mail step in Pipeline.

Thinking defensively about this, I believe that Code Valet would need some means of queuing these emails per user. Perhaps by overriding the mail step with something that would contact an internal Code Valet API which talks to Send Grid? More or less, there needs to be some way to prevent abuse.

[rtyler]

Got some Send Grid credentials, should be able to try this out shortly

[rtyler]

moved to CodeValet/master#5

[rtyler]

Actually on second thought, this ticket should be closed out when Kubernetes is providing the master image with the necessary environment variables.