Qpsmtpd: untaint config data passed to plugins

if QP passes in tainted data, such as a hostname that subsequently gets used to open a connection using IO::Socket, the plugin die because the information is tainted. Fix it once here, instead of in each plugin.
auth_vpopmaild: added taint checking to responses
replace run with separate run for the 2 common

deployment methods. Rather than having to edit the run file, it's much easier to rename the run file.
Moved qpsmtpd* into bin/
revert movement of qp bins to bin/

plugin dir, config dir, spool dir, all have different logic about where/how to find their config. The logic needs some untangling and unification before attempting this again.
Makefile.PL: added more disabled dependencies

DBI: commented out, but included for documentation's sake
summarize: strip out unprintable chars
Makefile.PL, added comments, stating where the

disabled plugins are used
summarize: move parts of main while loop to subs

and added POD
updated Changes