Merge with MySQL 5.1.50

- Changed to still use bcmp() in certain cases becasue
  - Faster for short unaligneed strings than memcmp()
  - Bettern when using valgrind
- Changed to use my_sprintf() instead of sprintf() to get higher portability for old systems
- Changed code to use MariaDB version of select->skip_record()
- Removed -%::SCCS/s.% from Makefile.am:s to remove automake warnings

sql/udf_example.c

@@ -1067,7 +1067,7 @@ char *myfunc_argument_name(UDF_INIT *initid __attribute__((unused)),
 {
   if (!args->attributes[0])
   {
-    null_value= 0;
+    *null_value= 1;
     return 0;
   }
   (*length)--; /* space for ending \0 (for debugging purposes) */