Allow InNewLine after Optional (because there is no ambiguity)

See: http://stackoverflow.com/questions/17791628/why-does-filehelpers-require-fieldoptional-even-after-fieldinnewline
(cherry picked from commit 4de9bafb8a769df758ae3b76862afb270c3c706c)
Merge pull request #12 from yserious/master

Allow InNewLine after Optional (because there is no ambiguity)