add fromFoldable as generic alternatives to some fromList methods
fix 2.9.9 (can't have context bounds and implciit parameter lists) (sorry larsh, one of these days I'll remember to check these myself :( )
Add NotNothing to witness a type is not Nothing
Use NotNothing in fromTryCatchThrowable

This now happens when Nothing as a subtype of Throwable is inferred:

    scala> \/.fromTryCatchThrowable("hello".toInt)
    <console>:14: error: ambiguous implicit values:
     both method isNothingAmb1 in object NotNothing of type => scalaz.NotNothing[Nothing]
     and method isNothingAmb2 in object NotNothing of type => scalaz.NotNothing[Nothing]
     match expected type scalaz.NotNothing[E]
                  \/.fromTryCatchThrowable("hello".toInt)
                                          ^

Which means there won't be runtime exceptions because an explicit type
parameter was forgotten.
Merge pull request #739 from stew/iset-fromfoldable

add fromFoldable as generic alternatives to some fromList methods
Merge pull request #746 from puffnfresh/notnothing

NotNothing