Merge pull request #358 from ricemery/space-age

Add file with expected interface. Refs #137

Author: ErikSchierboom

exercises/space-age/src/main/scala/SpaceAge.scala

@@ -0,0 +1,10 @@
+case class SpaceAge(val seconds: Long) {
+  val onEarth: Double = ???
+  val onMercury: Double = ???
+  val onVenus: Double = ???
+  val onMars: Double = ???
+  val onJupiter: Double = ???
+  val onSaturn: Double = ???
+  val onUranus: Double = ???
+  val onNeptune: Double = ???
+}