Revert #4273 + add tests

[CyberShadow]

#4273

https://issues.dlang.org/show_bug.cgi?id=16514

[dlang-bot]

Fix	Bugzilla	Description
✗	16514	std.socket methods are const, and thus cannot be overriden for SSLSocket, for example

[CyberShadow]

D'oh, wrong branch.

#4859

[wilzbach]

D'oh, wrong branch

Since a couple of weeks it's possible to change the target branch ;-)

[CyberShadow]

Really?? Thanks, that's awesome

[wilzbach]

See: https://github.com/blog/2224-change-the-base-branch-of-a-pull-request

[schveiguy]

Does it rebase though? I've switched locally targeting a different branch, but it pulls in all kinds of unrelated commits. Usually, you have to do a rebase onto the new branch in order to get the right result.

[CyberShadow]

I'd rather rebase manually than have the web service rewrite my branch though. Not having to create a new PR and update all links in shame is much bigger though.