Fixes #159: Add inclusion of cstdio to files using stdout, printf and etc.

[ryobg]

I stuck on this issue when trying to compiler with GCC 4.9.3 under Cygwin x64. Fix is just to add the necessary library reference. I think this should be reasonable fix for all build targets.

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[ryobg]

I signed it!

[googlebot]

CLAs look good, thanks!

[dmah42]

Please also add yourself to CONTRIBUTORS and AUTHORS in this patch

[EricWF]

LGTM. Thanks.