Mingw: Compile fixes for gcc 4.4

engine/src/C4InputValidation.cpp

@@ -25,6 +25,7 @@
 // FIXME: One should not have to include C4Game.h for pGUI
 #include <C4Game.h>
 #endif
+#include <cctype>
 
 namespace C4InVal
 	{

engine/src/C4MessageInput.cpp

@@ -31,6 +31,7 @@
 #include <C4Player.h>
 #include <C4GameLobby.h>
 #endif
+#include <cctype>
 
 // --------------------------------------------------
 // C4ChatInputDialog

engine/src/C4StartupPlrSelDlg.cpp

@@ -28,6 +28,7 @@
 #include <C4FileSelDlg.h>
 #include <C4Log.h>
 #endif
+#include <cctype>
 
 // font clrs
 const uint32_t ClrPlayerItem   = 0xff000000;

standard/src/StdFont.cpp

@@ -503,7 +503,7 @@ void CStdFont::Init(CStdVectorFont & VectorFont, DWORD dwHeight, DWORD dwFontWei
 		// convert using Win32 API
 		if (!fUTF8 && c>=128)
 			{
-			char cc[2] = { c, '\0' };
+			char cc[2] = { char(c), '\0' };
 			wchar_t outbuf[4];
 			if (MultiByteToWideChar(iCodePage, 0, cc, -1, outbuf, 4)) // 2do: Convert using proper codepage
 				{