[READY] Support MSVC 16

[micbou]

Add support for compiling with MSVC 16 (Visual Studio 2019).

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This change is 

[codecov]

Codecov Report

Merging #1249 into master will increase coverage by 0.2%.
The diff coverage is n/a.

@@            Coverage Diff            @@
##           master    #1249     +/-   ##
=========================================
+ Coverage   97.22%   97.42%   +0.2%     
=========================================
  Files          95       95             
  Lines        7389     7389             
  Branches      153      153             
=========================================
+ Hits         7184     7199     +15     
+ Misses        164      149     -15     
  Partials       41       41

[bstaletic]

Thanks.

Reviewed 5 of 5 files at r1.
Reviewable status: 1 of 2 LGTMs obtained

[puremourning]

Reviewed 5 of 5 files at r1.
Reviewable status: complete! 2 of 2 LGTMs obtained (waiting on @micbou)

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build.py, line 478 at r1 (raw file):

  # Set the architecture for the Visual Studio 16 generator.
  if OnWindows() and args.msvc == 16:

can we assume that this check should be >= 16 ?

[puremourning]

Reviewed 2 of 2 files at r2.
Reviewable status: 0 of 2 LGTMs obtained (and 2 stale)

[puremourning]

Reviewable status: 1 of 2 LGTMs obtained (and 1 stale)

[bstaletic]

Once again...

Reviewed 3 of 3 files at r3.
Reviewable status: 1 of 2 LGTMs obtained (and 1 stale)

[puremourning]

Reviewed 3 of 3 files at r3.
Reviewable status: complete! 2 of 2 LGTMs obtained

[mergify]

Thanks for sending a PR!

[mergify]

Thanks for sending a PR!