Add Shapeless to the sbt community build

[cunei]

This cab be done once the Shapeless build has been ported to sbt 1.0. Currently waiting on:
milessabin/shapeless#744

The following dependency should be fixed, according to the current community build:

[shapeless] [warn]      ::::::::::::::::::::::::::::::::::::::::::::::
[shapeless] [warn]      ::          UNRESOLVED DEPENDENCIES         ::
[shapeless] [warn]      ::::::::::::::::::::::::::::::::::::::::::::::
[shapeless] [warn]      :: org.scala-native#sbt-scala-native;0.3.0: not found
[shapeless] [warn]      ::::::::::::::::::::::::::::::::::::::::::::::
[shapeless] [warn]
[shapeless] [warn]      Note: Some unresolved dependencies have extra attributes.  Check that these dependencies exist with the requested attributes.
[shapeless] [warn]              org.scala-native:sbt-scala-native:0.3.0 (scalaVersion=2.12, sbtVersion=1.0)

[cunei]

Depends on scala-native/scala-native#915