bump salad & play versions
Merge pull request #57 from edofic/master

play 2.3.1 salat 1.9.8
Cross compile against 2.11.1 and 2.10.4
Merge remote-tracking branch 'upstream/master'

Conflicts:
	project/Build.scala
	src/main/scala/se/radley/plugin/salat/OptionsFromConfig.scala
	src/main/scala/se/radley/plugin/salat/SalatPlugin.scala