Workaround for GRADLE-2629 - pass daemon args via -Dorg.gradle.jvmArgs to daemon executer.
Fix log message.
Specify gradleUserHome via --gradle-user-home instead of -Dgradle.user.home, which is the most workingest option right now.

This means that we go back to the (non embedded) tests not working on Windows if the checkout has a space in its path. See the comment in the commit for more details.