Fix 17416 - Add REUSEPORT to std.socket

[0xEAB]

#8389 plus a reference link as requested by @CyberShadow.
Text has been adjusted to provide further explanations.

Further reading: https://stackoverflow.com/a/14388707

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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	17416	enhancement	SocketOption.REUSEPORT not available on linux

Testing this PR locally

If you don't have a local development environment setup, you can use Digger to test this PR:

dub run digger -- build "master + phobos#9082"

[thewilsonator]

Please retitle the commit message "Fix bugzilla issue 17416 - Add REUSEPORT to std.socket"