RFR : 8181205:JRE fails to load/register security providers when started from UNC pathname

[Seán Coffey]

The recent JDK-8163528 fix caused a regression for JDK binaries launched 
with a UNC pathname. We can use the Paths class to create the required 
File.  I managed to put a test together which should test this code path.

webrev : http://cr.openjdk.java.net/~coffeys/webrev.8181205/webrev/
JBS record : https://bugs.openjdk.java.net/browse/JDK-8181205

regards,
Sean.