www/nginx: nginx 1.12 doesn't work with XRID_HEADER option enabled

[Thomas Steen Rasmussen]

Hello,

Do not upgrade nginx to 1.12 if you have XRID_HEADER enabled. The
module is incompatible with nginx 1.12 and nginx will refuse to start
with the following error:

     nginx: [emerg] the duplicate "request_id" variable in 
/usr/local/etc/nginx/nginx.conf:16

where line 16 is where the http {} section starts. This happens even
with an empty http {} section.

I've opened this PR to address the issue:
https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=218956

I've also opened https://github.com/gabor/nginx-x-rid-header/pull/1
with the upstream which would make the module work, but would
require everyone to update their configs if merged.

If we just remove the module stuff will keep working with the
current configs, but the request IDs are no longer formatted as UUIDs.

/Thomas