Updated to use ReactiveExtensions in ProtocolProxy example
Updated to use ReactiveExtensions in ProtocolProxy example

`public delegate: ProtocolProxy` was missing `var`, so I fixed that - but also thought it would be good to show the actual `extension ReactiveExtensions` usage as it fits in with the example that's given further down
tonyarnold/Bond,ReactiveKit/Bond,SwiftBond/Bond,tonyarnold/Bond,ReactiveKit/Bond,SwiftBond/Bond