customize drop status code replacement on Windows

[rcbarnett-zz]

MODSEC-174: The "drop" action is not supported on Windows, it is replaced by a status 500.
It would be handy to use that specified status code instead of the hard-coded 500.

Ex: phase:1,status:400,drop,...
This would lead, under Windows, to a status 400

[rcbarnett-zz]

Original reporter: marcstern

[marcstern]

This is also (and especially) for Apache/Nginx on Windows