Update install instruction in manual
Update install instruction in manual

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