Add some additional checks required on Windows to keep all the checks in one place and to avoid exceptions later in the processing.

      Includes utility class to determine if platform is Windows and performance test case for alternative implementations.

git-svn-id: https://svn.apache.org/repos/asf/tomcat/tc8.5.x/trunk@1809673 13f79535-47bb-0310-9956-ffa450edef68