Update the README to not mention ponyc-master packages, and mention DNF (the Yum rewrite) (#1713)
Update the README to not mention ponyc-master packages, and mention DNF (the Yum rewrite) (#1713)

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Perelandric/ponyc,boemmels/ponyc,ponylang/ponyc,Perelandric/ponyc,mkfifo/ponyc,dipinhora/ponyc,jemc/ponyc,dipinhora/ponyc,dipinhora/ponyc,kulibali/ponyc,jemc/ponyc,Theodus/ponyc,mkfifo/ponyc,boemmels/ponyc,mkfifo/ponyc,Theodus/ponyc,Theodus/ponyc,sgebbie/ponyc,Perelandric/ponyc,kulibali/ponyc,jemc/ponyc,sgebbie/ponyc,Theodus/ponyc,mkfifo/ponyc,kulibali/ponyc,CausalityLtd/ponyc,cquinn/ponyc,boemmels/ponyc,sgebbie/ponyc,boemmels/ponyc,sgebbie/ponyc,cquinn/ponyc,Praetonus/ponyc,ponylang/ponyc,cquinn/ponyc,Perelandric/ponyc,boemmels/ponyc,cquinn/ponyc,sgebbie/ponyc,mkfifo/ponyc,Perelandric/ponyc,ponylang/ponyc,Praetonus/ponyc,kulibali/ponyc,CausalityLtd/ponyc,Praetonus/ponyc,Praetonus/ponyc,CausalityLtd/ponyc,Theodus/ponyc