Doesn't build with new xcode

[vantassell]

It looks like there's an error when compiling with the new version of Xcode (8.3).

SwiftDDP.DDPEvents.swift:62 - public var onConnected: Completion = Completion(callback: {session in log.info("connected with session: \(session)")})

Ambiguous use of init(callback:)

[robertzhang]

May be you can revise DDPEvents.swift file in SwiftDDP source code. Just like this:

public var onConnected: Completion = Completion(callback: {(session:String) in log.info("connected with session: (session)")})

[yvdorofeev]

#98