Updating play2-java-jpa

@hamiltont @richdougherty I've updated the Play JPA project.
Travis validation build seems ok: https://travis-ci.org/donovanmuller/FrameworkBenchmarks/builds/33564344

Have tried to make the changes consistent with those made in [play2-java-ebean](TechEmpower/FrameworkBenchmarks/tree/master/frameworks/Java/play2-java/play2-java-ebean)
I made a mistake in the `generate_config.py` file, so this needs to be `Full`. I've updated the `generate_config.py` in #1061 to generate the `benchmark_config` files properly (see commit https://github.com/richdougherty/FrameworkBenchmarks/commit/cc4dbdf9c7c033cbb359f52cf2d029c9b3d0dd60).