Release notes 0.20.0

Bitcoin ABC version 0.20.0 is now available from:

https://download.bitcoinabc.org/0.20.0/

This release includes the following features and fixes: - Support for Nov 2019 upgrade features, as detailed at https://github.com/bitcoincashorg/bitcoincash.org/blob/master/spec/2019-11-15-upgrade.md - Schnorr signatures for OP_CHECKMULTISIG(VERIFY): https://github.com/bitcoincashorg/bitcoincash.org/blob/master/spec/2019-11-15-schnorrmultisig.md - Enforce MINIMALDATA in script: https://github.com/bitcoincashorg/bitcoincash.org/blob/master/spec/2019-11-15-minimaldata.md - Bump automatic replay protection to May 2020 upgrade. - Searching by transaction ID is now available in bitcoin-qt. - Minor bug fixes.