6.11 typo?

Hi,
This commit https://github.com/tecnickcom/TCPDF/commit/2441f1dc includes a change at line 2910 of tcpdf.php that seems out of place, and effectively prevents compression from happening.

Was that some debugging code that got left in?

```diff
- $this->compress = false;
+ $this->compress = false; return;
```