ALLJOYN-2100 Increase thread stack size on Windows for Java VM compatibility

Change the stack size from 80k to 256k. Windows was likely rounding
up to 128k anyway, due to system allocation granularity, but 128k
has been marginal with some Java VMs.

Change-Id: Id9deb60cddc219f42db681677dc8b2dfd8c0a5c9