Display system properties
Fix sbt Play plugin version

Presumably due to some change of environment on my machine, I was
encountering a build failure combined with the error:

This project uses Play 2.1.2!
Update the Play sbt-plugin version to 2.1.1 (usually in project/plugins.sbt)

Applying this changed enabled the project to build cleanly again
with play clean dist.
Fix syntax error.
OOMs don't actually exhaust the heap