Since commit 37182ce2f3 the module was not present in static builds
because due to an invalid "ngx_module_type" the module was not added to
objs/ngx_modules.c.

This commit will fix the problem by setting the correct module type
"HTTP_FILTER" [Link 1].

Link 1: https://www.nginx.com/resources/wiki/extending/new_config/#key-ngx_module_type
Gentoo-Bug: https://bugs.gentoo.org/593450
Fixes: https://github.com/masterzen/nginx-upload-progress-module/issues/50

Addition of a header filter to track HTTP errors and return
the right status to upload progress probes.

 * First version