[8u40] review request: RT-38475: Enable JavaFX to build with VS 2012 and VS 2013

[Kevin Rushforth]

Dave H & Dave D,

Please review the following to enable building with VS2012:

JIRA:  https://javafx-jira.kenai.com/browse/RT-38475
Webrev:  http://cr.openjdk.java.net/~kcr/RT-38475/webrev.00/

Note that the default is still VS2010 and will remain so. This is both 
for developer convenience and in support of the ongoing compiler upgrade 
effort for JDK 9.

-- Kevin