Stream is Cojoin and Cobind
LazyOption is Cojoin and Cobind
move cobindAssociative from Comonad
add cojoin test
add Function1Cojoin
Merge pull request #388 from xuwei-k/function1cojoin

add Function1Cojoin
Merge pull request #387 from xuwei-k/req/cojoin-cobind

Cojoin and Cobind instances