before, if the mail content-type was text, it would not consider the
content encoding, only if it was multipart.
now this step on the mail parsing is performed both on multipart mails
and in text mails
the problem was that it was declared a byte array (txt) with
essentially size 0 and calling Read(txt). Since Read reads n
bytes up to sizeof(txt), nothing was being read.
now, there is only one binary that starts both servers,
making them use the same SQL connection.
this commit also added some `defer tx.Commit()` to ensure
all the transactions were closed
- Move mail functions to its own packages;
- Move bigger router functions to its own functions, and separate
router creation from main function;
- Edit the algorithm that choses the format will be chosen with
regards to format preference to a simples one.
