Patch v0.3

CHANGES v0.3
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* Product image displayed on list
* Extensions checks if product is in stock – if it's not then it's show same error as it wasn't found. 
* Extension checks if product has setup minimal quantity allowed with increments usage (i.e. sold only in packages of 10 pcs): if it is then extension's replacing InnerHTML in <strong>td.qty</strong> which normally contains <strong>INPUT</strong> with a <strong>SELECT</strong> with values incrementation. 
* Extension checks if product normal price is bigger than final price – if it is then extension's adding class name .old-price to price, and additionally displays final price (most often – special price), if it's not then show price in normal way. 
* Polish language pack.

TO DO 
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* More testing on sample data for Magento 1.8 
* Test for any versions of Magento that matter this days (help really apprieciated) 
* Find a way to store products added to list in some session, so if adding fails then list stays as it was - <strong>Contribution seriously appreciated</strong>
* Separate messages for errors with sku/product name which caused the error – many more possibilites to highlight product, etc.
* <strike>Block Enter key to process adding to cart – type="submit"</strike>
* Some CSS fixes for Default Magento theme (border, width %, etc.)