Documented the "--without-http_tunnel_module" configure option.

[ThrRip]

Proposed changes

The --without-http_tunnel_module option for the configure script was declared in nginx/auto/options but not documented. This PR adds it to the configure options documentation page.

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[pluknet]

Thanks for the patch.
I think we are good to shorten the description by removing the CONNECT link, it is provided is the module.

[pluknet]

Merged, thanks.