added examples/ to extra-doc-files
added a link to Newton's method example in Control.Comonad.Trans.Coiter
added link to example in Control.Monad.Free.TH
added link to example in Control.Monad.Trans.Iter
added link to example in Control.Applicative.Free
make use of runAp_ in example
[Ap] Field's functoriality is irrelevant
Merge pull request #59 from fizruk/link-examples

Links to examples from modules documentation