Fixes build with GCC 4.7, as well as the gold linker.

--- main.cpp
+++ main.cpp
@@ -22,6 +22,7 @@
 #include <signal.h>
 #include <sys/stat.h>
 #include <pwd.h>
+#include <unistd.h>
 #include "dbus.h"
 #include "notifywidget.h"
 #include "notifyarea.h"
--- notifyarea.cpp
+++ notifyarea.cpp
@@ -22,6 +22,7 @@
 #include <QSystemTrayIcon> //alex
 #include <QDesktopWidget>
 #include <fstream>
+#include <unistd.h>
 #include "notifyarea.h"
 #include "notifywidget.h"
 #include "dbus.h"
--- qtnotifydaemon.pro
+++ qtnotifydaemon.pro
@@ -13,6 +13,7 @@
 INCLUDEPATH += .
 QT += dbus
 RESOURCES += images.qrc
+LIBS += -lX11
 
 # Input
 SOURCES += main.cpp notifywidget.cpp dbus.cpp notifyarea.cpp message.cpp