Fix debug build Pair ambiguity on Windows
Fix debug build Pair ambiguity on Windows

Affects native windows builds (and possibly OSX) when the DEBUG
preprocessor is defined.

Justaphf/BitcoinUnlimited,BitcoinUnlimited/BitcoinUnlimited,BitcoinUnlimited/BitcoinUnlimited,Bitcoin-com/BUcash,Justaphf/BitcoinUnlimited,Bitcoin-com/BUcash,Bitcoin-com/BUcash,Justaphf/BitcoinUnlimited,BitcoinUnlimited/BitcoinUnlimited,Justaphf/BitcoinUnlimited,Justaphf/BitcoinUnlimited,Bitcoin-com/BUcash,Bitcoin-com/BUcash,BitcoinUnlimited/BitcoinUnlimited,BitcoinUnlimited/BitcoinUnlimited,BitcoinUnlimited/BitcoinUnlimited,Justaphf/BitcoinUnlimited,Bitcoin-com/BUcash