update email template

[StephanieBr]

Button is now in a table since it breaks in outlook otherwise.

[jace]

This looks all right, but I'll need to see the sample email in my inbox to judge properly. Does someone have this in a development instance?

[jace]

I'm waiting on sample emails to proceed with the review.

[jace]

There is too much whitespace in this template.

[vidya-ram]

Fixed the width of the wrapper and content box

[CLAassistant]

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