Fix MSVC version for VS2019.

Microsoft's version change was not as previously advertised.

@dcthompson

@ben.boeckel this fixes boost compiles with MSVC 2017

https://en.wikipedia.org/wiki/Microsoft_Visual_C%2B%2B#Internal_version_numbering

+1 (pending dashboards)

No dashboards here, only through pv or cmb superbuild. Need @ben.boeckel to merge, too, no robot.

There's a robot here :) . But you can make an MR in ParaView's and CMB's superbuilds with a bump of the superbuild to this commit; buildbot will check your fork for submodule references before giving up (something I need to allow for gitlab-ci now that I think about it…).

Do: merge

merged

mentioned in commit af2d6278