Added explicit cast to char in ToUTF8::windows_XXXX tables.

Added explicit cast to char, without that gcc 4.7 (with default settings)
is showing a lot of:

narrowing conversion of ‘...’ from ‘int’ to ‘char’ inside { } is ill-formed in C++11 [-Wnarrowing]

warnings.

components/to_utf8/gen_iconv.cpp

@@ -12,7 +12,7 @@ void tab() { cout << "   "; }
 // write one number with a space in front of it and a comma after it
 void num(unsigned char i, bool last)
 {
-  cout << " 0x" << (unsigned)i;
+  cout << " (char)0x" << (unsigned)i;
   if(!last) cout << ",";
 }