Added implicit Python conversion of time_duration_t
Added implicit Python conversion of time_duration_t

jwakely/ledger,afh/ledger,afh/ledger,duncanmortimer/ledger,duncanmortimer/ledger,jwakely/ledger,duncanmortimer/ledger,jwakely/ledger,jwakely/ledger,ledger/ledger,afh/ledger,jwakely/ledger,paulbdavis/ledger,paulbdavis/ledger,duncanmortimer/ledger,duncanmortimer/ledger,paulbdavis/ledger,jwakely/ledger,afh/ledger,ledger/ledger,paulbdavis/ledger,duncanmortimer/ledger,duncanmortimer/ledger,afh/ledger,ledger/ledger,ledger/ledger,paulbdavis/ledger,paulbdavis/ledger,ledger/ledger,jwakely/ledger,paulbdavis/ledger