[ANN] DkML 2.1.2 and opam 2.2.0

[jbeckford]

@dra27

or only wants MSVC switches for OCaml 4.14 and earlier.

For completeness for users who already have an existing VS 2019, what is the command line incantation to do that?

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Unrelated: DkML uses wget not curl, so there is no urgency getting opam 2.2.1 into DkML.