Method realloc

sql/sql_string.h:748–754

  bool real_alloc(size_t arg_length);  // Empties old string
  bool realloc_raw(size_t arg_length);
  bool realloc(size_t arg_length)
  {
    if (realloc_raw(arg_length+1))
      return TRUE;
    Ptr[arg_length]= 0; // This make other funcs shorter
    return FALSE;
  }
  bool realloc_with_extra(size_t arg_length)
  {
    if (extra_alloc < 4096)