optimize alignList
add These align unalign tests
add EphemeralStream#take, EphemeralStream#takeWhile
tests for EphemeralStream#take, EphemeralStream#takeWhile
fix EphemeralStream#unzip type constraint
add EphemeralStream unzip zip test
Enhanced timed Future so it would not block the Future`s execution thread pool, but instead will use scheduled executor to notify timeout.
Fix #371. Call-by-need instead of call-by-name.
Merge pull request #490 from xuwei-k/alignList

optimize alignList
Merge pull request #491 from xuwei-k/EphemeralStream-take-takeWhile

add EphemeralStream#take, EphemeralStream#takeWhile
Merge pull request #492 from xuwei-k/EphemeralStream-unzip

fix EphemeralStream#unzip type constraint
Merge pull request #493 from Spinoco/scalaz-seven-contrib

Enhanced timed Future so it would not block the Future`s execution threa...