Fix FutureTest code.

Adding methods to package object trumps the ones of the
same name formerly imported.
fix take and takeViaUnfold - don't initialize tail for last taken element
another version of zipAll/zipWithAll which doesn't make finite streams infinite
fix take and takeViaUnfold - don't initialize tail for last taken element
Also hide scala std lib Some, None, Right and Left
Merge pull request #283 from OleTraveler/hide-stdlib

Also hide scala std lib Some, None, Right and Left
Fixed syntax
Merge pull request #287 from AlexanderDaniel/answerkey_monad_exercise6

Fixed syntax in answer key for monads exercise 6
Monads: compose in terms of join
Merge pull request #290 from AlexanderDaniel/composeInTermsOfJoin

Monads: compose in terms of join
Merge pull request #272 from paulp/iomonad-fix

Fix FutureTest code.
Merge pull request #270 from jozic/fix-takeViaUnfold

fix takeViaUnfold - decrease n and don't initialize tail for last taken element
Issue #281
Merge pull request #291 from orionll/patch-2

Issue #281
added note about RNG.Simple <=> RNG.SimpleRNG discrepancy
Merge remote-tracking branch 'origin/master'
Delete 7.answer.scala
Rename 9.answer.scala to 7.answer.scala
Delete 8.answer.scala
Rename 10.answer.scala to 8.answer.scala