Remove magic "localhost" value from z_dispatcher:drop_port/1
Remove magic "localhost" value from z_dispatcher:drop_port/1

This behaviour made the fallback site always be served on localhost;
thus preventing any other site from taking this domain.

Fixes #422

erlanger-ru/erlanger-ru.meta,erlanger-ru/erlanger-ru.meta,erlanger-ru/erlanger-ru.meta,erlanger-ru/erlanger-ru.meta,erlanger-ru/erlanger-ru.meta