Fix: Windows and/or includes (iso646)

[ax3l]

Summary

Add missing includes to AMReX_Extension.H, which pulls the <iso646.h> include on Windows for support for and/or.

Additional background

Seen with Clang 11.0.0 on x64 Windows with Visual Studio 2017 on conda-forge during a WarpX build.

See also #947

Checklist

The proposed changes:

• fix a bug or incorrect behavior in AMReX
• add new capabilities to AMReX
• changes answers in the test suite to more than roundoff level
• are likely to significantly affect the results of downstream AMReX users
• are described in the proposed changes to the AMReX documentation, if appropriate

[ax3l]

Hm, patch looks needed but the original issue I saw with VS2017 and Clang11 on CF is not fixed yet.

@WeiqunZhang It looks like even other major libs gave up on and/or/not keywords: nlohmann/json#2259

Background:

• Clang-Cl does not work well with the iso646 header in C++ mode: Fail to build when including json.hpp as a system include nlohmann/json#1818 (comment) (weirdly, works with VS2019 + Clang 10 in CI)
• And even if it does, some Windows headers use these keywords so one cannot define them always: http://lists.llvm.org/pipermail/cfe-commits/Week-of-Mon-20170522/193579.html

Maybe VS2019 just fixed the need for this header... https://docs.microsoft.com/en-us/cpp/standard-library/ciso646?view=msvc-160&viewFallbackFrom=vs-2019