Add explanation on how to validate documentation examples
Add explanation on how to validate documentation examples

by specially marking @smallexample, which will be used by DocTests.py
duncanmortimer/ledger,paulbdavis/ledger,jwakely/ledger,paulbdavis/ledger,jwakely/ledger,paulbdavis/ledger,duncanmortimer/ledger,paulbdavis/ledger,ledger/ledger,jwakely/ledger,duncanmortimer/ledger,duncanmortimer/ledger,paulbdavis/ledger,afh/ledger,afh/ledger,afh/ledger,duncanmortimer/ledger,duncanmortimer/ledger,jwakely/ledger,afh/ledger,paulbdavis/ledger,jwakely/ledger,ledger/ledger,paulbdavis/ledger,jwakely/ledger,ledger/ledger,ledger/ledger,afh/ledger,duncanmortimer/ledger,ledger/ledger,jwakely/ledger