Allow customized subset of connection types

Added a new method signature handshake(allowedConnectionTypes, ext). This method can be used to disable using certain connection types supported by the library.

Updated to support Swift Package Manager

0.5.1

Updated to support Swift Package Manager

Updated to support Swift 5.0

0.5.0

Swift 5.0 support and retroactively added Swift 4.0 as supported

Project forked and renamed GFayeSwift for Swift 4.2

Project forked from hamin/FayeSwift, renamed GFayeSwift, and converted to Swift 4.2.