Update core/src/main/scala/scalaz/LazyOption.scala

Before patch, lazyNone.isDefined == true  and  lazySome(3).isDefined == false
Merge pull request #250 from refried/patch-5

Update core/src/main/scala/scalaz/LazyOption.scala
Remove tests for triple composition

Many test failures on Travis are actually caused by OOM while checking
'traverse.sequential fusion' on 'Triple composition traverse'.