Added C++ style guide.
Added C++ style guide.

Airbitz/libbitcoin,swansontec/libbitcoin,semyazza/libbitcoin,GroestlCoin/libgroestlcoin,libtetcoin/libtetcoin-consensus,BWallet/libbitcoin,swansontec/libbitcoin,semyazza/libbitcoin,Airbitz/libbitcoin,swansontec/libbitcoin,libmetrocoin/libmetrocoin-consensus,semyazza/libbitcoin,kaostao/libbitcoin,GroestlCoin/libgroestlcoin,Airbitz/libbitcoin,GroestlCoin/libgroestlcoin,libmetrocoin/libmetrocoin-consensus,kaostao/libbitcoin,BWallet/libbitcoin,libmetrocoin/libmetrocoin-consensus,GroestlCoin/libgroestlcoin,libmetrocoin/libmetrocoin-consensus,libtetcoin/libtetcoin-consensus,BWallet/libbitcoin,kaostao/libbitcoin,libtetcoin/libtetcoin-consensus,libtetcoin/libtetcoin-consensus,Airbitz/libbitcoin,libtetcoin/libtetcoin-consensus,kaostao/libbitcoin,libmetrocoin/libmetrocoin-consensus,BWallet/libbitcoin,swansontec/libbitcoin