Update example to work in Rails console

[RogerPodacter]

Fixes

Checklist

• [ x] I have made a material change to the repo (functionality, testing, spelling, grammar)
• [ x] I have read the [Contribution Guide] and my PR follows them.
• [ x] I updated my branch with the master branch.
• [ x] I have added tests that prove my fix is effective or that my feature works
• [ x] I have added necessary documentation about the functionality in the appropriate .md file
• [ x] I have added in line documentation to the code I modified

Short description of what this PR does:

Because Mail is used by Rails the "hello world" example doesn't work in the Rails console out of the box. This change fixes that and is also consistent with the existing reference to SendGrid::API which is also strictly speaking unnecessary if one is including this module in a class.

Perhaps there is another way to handle this but my view FWIW is that it's supremely important that simplest example work in the Rails console with no changes.

[SendGridDX]

All committers have signed the CLA.

[thinkingserious]

Hello @RogerPodacter,

Thanks again for the PR!

We want to show our appreciation by sending you some swag. Could you please fill out this form so we can send it to you? Thanks!

Team SendGrid DX

[RogerPodacter]

Done! Thank you and my pleasure!

…

On Thu, Sep 27, 2018 at 9:34 PM Elmer Thomas ***@***.***> wrote: Hello @RogerPodacter <https://github.com/RogerPodacter>, Thanks again for the PR! We want to show our appreciation by sending you some swag. Could you please fill out this form <https://dx.sendgrid.com/swag> so we can send it to you? Thanks! Team SendGrid DX — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#306 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AADnNlr1JuWOhfZ39lB74fHcS-NmFQY2ks5ufXy7gaJpZM4WgcCz> .