Added pending tests & adjusted songId type to Long.
refactor on tests definition
adjust assert method expresion
'Solution' trait created to hold data of the final solution
Better tests, solutions and less ambiguities.
More Long

+ allSongs: Seq[Long]
Mover el resto de los números a Solutions
Merge pull request #5 from fedesilva/more-in-test
Merge remote-tracking branch 'upstream/master'

Conflicts:
	src/test/scala/DuplicatesTest.scala
	src/test/scala/util/Solutions.scala
Merge branch 'master' into gpolito-impl

Conflicts:
	src/main/scala/Duplicates.scala
	src/test/scala/DuplicatesTest.scala
	src/test/scala/util/Solutions.scala