[Dovecot] whoson plugin for 2.0

[Chuck Cochems]

I have found a plugin at

ftp://ftp.ufanet.ru/pub/boco/dovecot/whoson-plugin/

I was able to make it function on a dovecot 1.2.8 server, by changing 
__attr_unused__ to ATTR_UNUSED and strlcpy to i_strocpy (since glibc 
doesn't HAVE strlcpy, on purpose).

However, it doesn't work with 2.1

this is, of course, because getenv() no longer functions lie it used to 
in plugins.

so i need a replacement for getenv("IP") and getenv("USER") to make this 
work.

i know, pop before SMTP is stupid, but the isp i'm doing this for hs 
customers that have used pop before smtp for ages.

so I MUST make a whoson plugin.

as i said, the remote ip and the email address are required to interface 
with whoson. (this is superior to DRAC, which just opens the IP)