Updated travis yml to workaround https://github.com/dotnet/cli/issues/3964
Updated travis yml to workaround https://github.com/dotnet/cli/issues/3964

OmniSharp/omnisharp-roslyn,DustinCampbell/omnisharp-roslyn,DustinCampbell/omnisharp-roslyn,OmniSharp/omnisharp-roslyn