added util methods for coverting IP address

steam/util/__init__.py

@@ -0,0 +1,9 @@
+import struct
+import socket
+
+
+def ip_from_int(ip):
+    return socket.inet_ntoa(struct.pack(">L", ip))
+
+def ip_to_int(ip):
+    return struct.unpack(">L", socket.inet_aton(ip))[0]