Merge pull request #34 from mfrancis95/ross

Added CocktailSort and GnomeSort plus tests
Added iterate() method.
Made iterate() a part of the Iterable interface, which List and Set now implement.
Revert "Made iterate() a part of the Iterable interface, which List and Set now implement."

This reverts commit faf7cc8bde8a0e977dc010be54c36e7227e69ce1.
Added ImmutableList.
Revert "Added ImmutableList."

This reverts commit 060ec898f0699e3cccb2a69efbbdb87b9e5a922f.
Merge pull request #35 from mfrancis95/ross

DoubleQueueStack and LinkedDeque
Fully implemented ArraySet.
Changed remove() from a void method to a boolean method.
Merge pull request #36 from mfrancis95/mike

iterate() and ArraySet
Merge branch 'master' into ross