[FIX] parse_number correctly setting _is_negative
[FIX] parse_number correctly setting _is_negative

darkdarkdragon/ripple-lib,ripple/ripple-lib,wilsonianb/ripple-lib,darkdarkdragon/ripple-lib,ripple/ripple-lib,ripple/ripple-lib,wilsonianb/ripple-lib,ripple/ripple-lib,darkdarkdragon/ripple-lib,wilsonianb/ripple-lib