fix treeInstance#foldMapRight1

previous version does not satisfy law
Foldable1[Tree] law test
Add cobind to Ephemeral stream & check laws.
Merge pull request #517 from possiblywrong/scalaz-seven

Add cobind to EphemeralStream & check laws.
fix EphemeralStream#tails
EphemeralStream inits & tails test
use cons instead of ##::
Merge pull request #526 from xuwei-k/tree-foldMapRight1

fix treeInstance#foldMapRight1