Merge pull request #1914 from Forostovec/fix/broken-link

BIP 70: fix link to payment request generator

Author: jonatack

bip-0070.mediawiki

@@ -302,7 +302,7 @@ Protocol Buffers : https://developers.google.com/protocol-buffers/
 
 ==Reference implementation==
 
-Create Payment Request generator : https://bitcoincore.org/~gavin/createpaymentrequest.php ([[https://github.com/gavinandresen/paymentrequest|source]])
+Create Payment Request generator : https://developer.bitcoin.org/examples/payment_processing.html ([[https://github.com/gavinandresen/paymentrequest|source]])
 
 BitcoinJ : https://bitcoinj.github.io/payment-protocol#introduction