#561 OneCLick fix for alternative payment methods and guest checkout and option to set the sepa flow default is sale

Update README.md

Fixed typo

added logo for adyen POS and not using a transparent gif to generate the size but just a class with a css widht height definition with a sprite img background

Added PayPal requriement

fix length field holder name, result URl fix for logger, added some license texts, cleanup code and remove die() statement in a catch statement

oneclick implemented billing agreement disable call to adyen, creditcardtype now set for CreditCard and Oneclick payment method, removed cron controller, added info and error logfile for info and error statements, fix save creditcard checkbox function