How to set up JMSpayment Bundle and add the paypal plugin

http://symfony2.ylly.fr/how-to-set-up-jmspayment-bundle-and-add-the-paypal-plugin-sebastien/

http://stackoverflow.com/questions/15191944/paypal-in-symfony2

https://github.com/Payum/Payum/blob/master/docs/supported-payments-and-other-libraries.md