Remove Guava and use JUnit assert (#170)
Remove Guava and use JUnit assert (#170)

* remove Guava and use JUnit assert

* reassign old to Collection.unmodifiable

* reassign variable expected

nickRm/xjava,jmluy/xjava,exercism/xjava,FridaTveit/xjava,jtigger/xjava,exercism/xjava,jmluy/xjava,FridaTveit/xjava,nickRm/xjava,jtigger/xjava