ADD] - Added a note in the welcome step of the installer as to what to do if the installer does not pass the welcome screen
[ENH] - Encode the subject and body in the list-unsubscribe header value
[MSC] - Overall fixes
[BUG] - Fix a bug in tracking URLs that would prevent transforming successive links on the same line
[CHG] - Transform HTML into plain text ONLY if the given input is HTML, otherwise leave it as is
[MSC] - Overall fixes
[UPD] - Updated composer packages
