Merge pull request #96 from Subv/patch-2

 Add the <arpa/inet.h> include to unix.h

include/enet/unix.h

@@ -9,6 +9,7 @@
 #include <sys/time.h>
 #include <sys/types.h>
 #include <sys/socket.h>
+#include <arpa/inet.h>
 #include <netinet/in.h>
 #include <unistd.h>
 

unix.c

@@ -8,7 +8,6 @@
 #include <sys/socket.h>
 #include <sys/ioctl.h>
 #include <sys/time.h>
-#include <arpa/inet.h>
 #include <netinet/tcp.h>
 #include <netdb.h>
 #include <unistd.h>