NegaScout

I had issues in 1.9 with v0.2.1, used CombinedParsers#master (v0.2.2) and it fixed the issue for now. The error trace was: ``` julia> using CombinedParsers [ Info: Precompiling CombinedParsers [5ae71ed2-6f8a-4ed1-b94f-e14e8158f19e]...