Added note about using MacPorts to install library dependencies.
Added note about using MacPorts to install library dependencies.

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