Added missing os_copyfile.c (doh!)

src/host/os_copyfile.c

@@ -0,0 +1,34 @@
+/**
+ * \file   os_copyfile.c
+ * \brief  Copy a file from one location to another.
+ * \author Copyright (c) 2002-2008 Jason Perkins and the Premake project
+ */
+
+#include "premake.h"
+
+
+int os_copyfile(lua_State* L)
+{
+	int z;
+	const char* src = luaL_checkstring(L, 1);
+	const char* dst = luaL_checkstring(L, 2);
+
+#if PLATFORM_WINDOWS
+	z = CopyFile(src, dst, FALSE);
+#else
+	luaL_pushfstring(L, "cp %s %s", src, dst);
+	z = (system(lua_tostring(L, -1)) == 0);
+#endif
+
+	if (!z)
+	{
+		lua_pushnil(L);
+		lua_pushfstring(L, "unable to copy file to '%s'", dst);
+		return 2;
+	}
+	else
+	{
+		lua_pushboolean(L, 1);
+		return 1;
+	}
+}