[FIX] - sale_order_report: Fixes #7 missing default icon.

No default module icon
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Modified module information to display default icon instead of an error image.
![captura de pantalla de 2014-07-18 08 33 14](https://cloud.githubusercontent.com/assets/7594716/3629468/ea878140-0ea0-11e4-8d51-15265e149d1d.png)