[Issue 24785] Add explicit template arguments for lambdas

[d-bugmail at puremagic.com]

https://issues.dlang.org/show_bug.cgi?id=24785

--- Comment #1 from Bolpat <qs.il.paperinik at gmail.com> ---
This would enable things like:
```d
allSatisfy!(function template(T) => is(T : Object), ...)
```

Although requiring some modifications to `allSatisfy` to make it call a
function pointer or delegate with zero arguments if given one via `alias`.

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