Update README.md (#699)
Update README.md (#699)

Example of how to install a flow-typed definition does not include actual command line definition format. Updated to include.
orlandoc01/flow-typed,echenley/flow-typed,doberkofler/flow-typed,flowtype/flow-typed,mkscrg/flow-typed,flowtype/flow-typed,hansonw/flow-typed,gaborsar/flow-typed,splodingsocks/FlowTyped,orlandoc01/flow-typed,mwalkerwells/flow-typed,davidohayon669/flow-typed,gaborsar/flow-typed,splodingsocks/FlowTyped,mkscrg/flow-typed,davidohayon669/flow-typed,echenley/flow-typed,doberkofler/flow-typed,mwalkerwells/flow-typed,hansonw/flow-typed