Add jexl to report subject and body; include variables passed from gsh script

When getting an email for a report, it would be improved by including more information to it, so the recipient can decide the urgency of viewing the report.For example, including the count of non-compliant members, so staff can see it directly in the email.

It can also be improved by using real jexl variables, and not the $$ syntax which is more limited in expressiveness.