Working on adding a aggregated values to each email for:

Number of direct replys,
Number of chained replys.

Some emails that are in reply to other emails, don't have an specific
email id in the inReplyTo field.

Here is an example:
[ "Dean Gaudet's message of \"Fri, 4 Jun 1999 10:13:25 -0700 (PDT)\""]
[ "Tony Finch's message of \"Fri, 4 Jun 1999 19:16:57 +0100\""]