Fix issue 6895 std.traits.isCovariantWith doesn't work for function, …

[Darredevil]

…function pointer and delegate

https://issues.dlang.org/show_bug.cgi?id=6895

[dlang-bot]

Thanks for your pull request, @Darredevil! We are looking forward to reviewing it, and you should be hearing from a maintainer soon.

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Bugzilla references

Auto-close	Bugzilla	Description
✓	6895	std.traits.isCovariantWith doesn't work for function, function pointer and delegate

[RazvanN7]

LGTM