Updated all benchmarks to Play 2.3.6 and Scala 2.11.4.

Updated Ebean benchmarks to include missing tests as well as include HikariCP version.
Moved `/plaintext` tests from JPA/Ebean benchmarks to the `play2-java` benchmark as per https://github.com/TechEmpower/FrameworkBenchmarks/pull/1149#dis
Added BoneCP qualifier as per https://github.com/TechEmpower/FrameworkBenchmarks/pull/1149#discussion_r19584629 and changed names accordingly.
Good idea to use action composition here but we may want to keep an eye on how this affects performance. I don't think I've profiled action composition, so it's possible Play might use reflection in an inefficient way. If action composition slows things down then of course we should try to fix Play if possible.

Just something to keep in mind if we see a drop in performance for the JSON test.