Fixed #47: MAGE-6659: Transactional Emails logo feature interacts incorrectly with Database as media storage
Moved _fileExists method from Mage_Catalog_Model_Product_Image into Mage_Core_Helper_File_Storage, call the helper method when getting logo for email to save it to FS from DB if it does not exist
Merge pull request #47 from magento/steverice-47

MAGE-6659: Transactional Emails logo feature interacts incorrectly with Database as media storage