Update README.md
Upgraded to Play 2.3.0-RC2

* Added cross build support for Scala 2.11
* Updated a few other library versions

Conflicts:
	project/Play2-ReactiveMongo.scala
Use Play actor system

Fixes #88

By using the Play actor system, we avoid the thread leak created by not
shutting the mongo driver down.

Also, made sure the mongo driver is shut down.
index on master: f316233 Merge pull request #87 from jroper/play23
0.10.5.akka23-SNAPSHOT