release-2.2

This release allows the user to use a different email-template on a per-feed basis. This change was implemented as a pull-request by @jcvernaleo.

Other than the new configuration-option there have only been a small number of changes compared to the previous release - I fixed some of the internal implementation to resolve 100% of the "complexity" issues reported upon the go report card, allowing the application to receive a perfect score.