Update local test-project to work against local sbt-native-packager with play settings.

* Default to sbt 0.13 build now
* Remove reference to released version of sbt-native-packager in test-project.
Handle the case where java arguments may have spaces.

* Add appropriate quotes to make sure java arguments (-D) are correctly handled.
* Add a test to validate the fix works

Fixes #205
Merge pull request #207 from sbt/wip/fix-205

Handle spaces in java arguments properly