RFR: JDK-8202557: OpenJDK fails to start in Windows 7 and 8.1 after upgrading compiler to VC 2017

[Erik Joelsson]

With the new VS2017 toolchain Microsoft has changed how the C++ 
libraries work. In addition to the old msvcr* and msvcp* dll files, we 
now have a big lot of UCRT dlls as well. These files are also 
redistributable but are found in the Windows Kit rather than the Visual 
Studio installation. On modern and updated Windows systems these files 
should be present on the system, but to support older and non updated 
OSes, you can bundle them with your app, just like we already do with 
the old msvc* files.

This patch does the following:

* Adds the UCRT dll files to the windows devkit
* Adds logic in configure for finding the correct UCRT redist dir if the 
toolchain version needs it
* Makes the build copy the files into java.base
* Makes sure any of these files are filtered out of any imported module 
to avoid conflicts

Bug: https://bugs.openjdk.java.net/browse/JDK-8202557

Webrev: http://cr.openjdk.java.net/~erikj/8202557/webrev.01/index.html

/Erik