[TASK|FUNCTION|FEATURE] Introduce ability to keyworkEntitie(s) to save original_email content
Basically the keyword entity can chose if the mails refering it should be saved with html or without.
The reason for this is because of some emails containing table and data depending on HTML tags, which if
stringidied makes them unreadable.

Resolves: #30
Related: #20, #19, #1
Releases: 1.2.x