Setting version to 2.3.0-RC4
Setting version to 2.3.0-RC4

alexarchambault/shapeless,lukasz-golebiewski/shapeless,triggerNZ/shapeless,liff/shapeless,lambdista/shapeless,wheaties/shapeless,khronnuz/shapeless,milessabin/shapeless,fthomas/shapeless,isaka/shapeless