Support mail filtering by envelope :detail (+ part in mail addresses)

To enable users to manage mailfilters by envelope :detail without access to custom filters, I added a 4th filter type to the mailfilter selection and added required changes to filter generation, sieve script templates and postfix config.

https://www.howtoforge.com/community/threads/filter-mails-by-detail.78046/

Example for a filter:

Address Detail is 'blog' -> move to Blogs
--> all mails sent to user+blog@domain.com get moved into Blogs

Address Detail begins with 'social' -> set read
--> all mails to user+social-fb@domain.com, user+social-twitter@domain.com, ... are set as read