added support to zmq_device

Sources/ZeroMQKit/Device.swift

@@ -0,0 +1,57 @@
+// Proxy.swift
+//
+// The MIT License (MIT)
+//
+// Copyright (c) 2015 Zewo
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+
+import CZeroMQ
+
+public enum DeviceType {
+    case streamer
+    case forwarder
+    case queue
+}
+
+extension DeviceType {
+    init?(rawValue: Int32) {
+        switch rawValue {
+        case ZMQ_STREAMER:  self = .streamer
+        case ZMQ_FORWARDER: self = .forwarder
+        case ZMQ_QUEUE:     self = .queue
+        default:            return nil
+        }
+    }
+}
+
+extension DeviceType {
+    var rawValue: Int32 {
+        switch self {
+        case .streamer: return ZMQ_STREAMER
+        case .forwarder: return ZMQ_FORWARDER
+        case .queue: return ZMQ_QUEUE
+        }
+    }
+}
+
+public func device(type: DeviceType, frontend: Socket, backend: Socket) {
+    zmq_device(type.rawValue, frontend.socket, backend.socket)
+}
+