[doc] Improve @smallexample command line parsing
[doc] Improve @smallexample command line parsing

by using Python shlex.

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