allow to use the new address format when sending a payment

allow to use the new address format when signing and verifying a message

allow to configure in the GUI if addresses should be displayed in the new or old format

provide a command line argument to convert the old format to the new and vice versa

BUIP070: Support BitPay's new Bitcoin Cash address format in BUCashSubmitted on 8th November 2017 by torusJKLBitcoin and Bitcoin Cash share the same address format.This had the effect that users have sent BTC or BCH to an address that was used on the other chain such that if the other party does not recognize that chain the coins are "lost".In addition users have sent BCH to SegWit addresses making them unspendable on the BCH chain even if the owner had the private key.Implement a new address format that only needs minimal changes on the wallet side but would make the addresses distinguishable from each other such that users do not send funds to addresses from wallets that use the BTC chain.Use the new address format which has been implemented by BitPay in their Copay wallet by changing the version byte of the address.The version byte is set to 28 for p2pkh addresses and 40 for p2sh addresses.Reference links:Example p2pkhOld format: 1422ciKobfkK2Zk3TpNSebmEBEtDHEP5nGNew format: CKUvBkfsUiiqvheU9ZhNE7PFoN6d99oMooExample p2shOld format: 36XTMVtgJqqNYymsSvRonpUsbZRGkm1jvXNew format: HBMZpJKmAA43B9euJc5xmD1QdDSHh9j6kRBUCash should develop the following:edit: added command line argument to convert address formats