title: Grouped UITableView shows blank space when section is empty
body: <p>I have a grouped UITableView where not all sections may be displayed at once, the table is driven by some data that not every record may have.  My trouble is that the records that don't have certain sections show up as blank spaces in the table.
  There are no footers/headers.  Anything I've missed?</p>
  <pre><code>- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
  // Return the number of rows in the section.
  return [self getRowCount:section];
  }
  
  
  // Customize the appearance of table view cells.
  - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
  
  static NSString *CellIdentifier = @&quot;Cell&quot;;
  
  UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
  if (cell == nil) {
      cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease];
  }
  
  cell.textLabel.text = [NSString stringWithFormat:@&quot;section: %d row: %d&quot;,indexPath.section,indexPath.row];
  // Configure the cell...
  
  return cell;
  }
  
  - (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath {
      
      float height = 0.0;
      
      if([self getRowCount:indexPath.section] != 0){
          height = kDefaultRowHeight;
      }
      
      return height;
      
  }
  </code></pre>