Add missing imports pointed out by Ketmar

src/client.d

@@ -258,6 +258,8 @@ Options:
 
 TcpSocket createSocket(ushort port)
 {
+	import core.time : dur;
+
 	TcpSocket socket = new TcpSocket(AddressFamily.INET);
 	socket.setOption(SocketOptionLevel.SOCKET, SocketOption.RCVTIMEO, dur!"seconds"(5));
 	socket.connect(new InternetAddress("localhost", port));

src/server.d

@@ -29,6 +29,7 @@ import std.process;
 import std.datetime;
 import std.conv;
 import std.allocator;
+import std.exception : enforce;
 
 import core.memory;