Clean up includes.

stepmania/src/arch/ArchHooks/ArchHooks_darwin.cpp

@@ -20,7 +20,6 @@
 #include <Carbon/Carbon.h>
 #undef Random_
 #include <mach/thread_act.h>
-#include <signal.h>
 #include <sys/types.h>
 #include <sys/sysctl.h>
 

stepmania/src/arch/LoadingWindow/LoadingWindow_Cocoa.mm

@@ -8,7 +8,7 @@
  */
 
 /* This is really dumb. I don't know why it is needed all of a sudden */
-#include <math.h>
+#include <cmath>
 #ifndef scalb
 #define scalb(x, n) scalbn(x, n)
 #endif

stepmania/src/arch/MemoryCard/MemoryCardDriver_Linux.cpp

@@ -4,9 +4,9 @@
 #include "RageUtil.h"
 #include "RageFileManager.h"
 
-#include <stdio.h>
-#include <string.h>
-#include <errno.h>
+#include <cstdio>
+#include <cstring>
+#include <cerrno>
 #include <unistd.h>
 #include <fcntl.h>
 #include <linux/types.h>

stepmania/src/arch/MovieTexture/MovieTexture_FFMpeg.cpp

@@ -10,7 +10,7 @@
 #include "SDL_endian.h"
 #include "PrefsManager.h"
 
-#include <errno.h>
+#include <cerrno>
 
 namespace avcodec
 {

stepmania/src/arch/Sound/RageSoundDriver_QT1.cpp

@@ -14,7 +14,7 @@
 #include "RageUtil.h"
 #include "RageLog.h"
 #include <QuickTime/QuickTime.h>
-#include <stdlib.h>
+#include <cstdlib>
 /* Ugh */
 using namespace QT;