Remove screenshot from README
Remove screenshot from README

billCTG/braintree_ios,braintree/braintree_ios,braintree/braintree_ios,apascual/braintree_ios,apascual/braintree_ios,billCTG/braintree_ios,billCTG/braintree_ios,braintree/braintree_ios,billCTG/braintree_ios,apascual/braintree_ios,braintree/braintree_ios,billCTG/braintree_ios,apascual/braintree_ios