Release notes 0.18.7

Bitcoin ABC version 0.18.7 is now available from:

https://download.bitcoinabc.org/0.18.7/

This release includes the following features and fixes: - Add the -walletdir option to configure the directory in which the wallet files are stored. An absolute path should be used. - Add the -debuglogfile option to change the path of the debug log file. - Fix issue where bitcoin-qt fails to launch for Qt versions >=5.11 - Minimum supported version of gcc bumped to 4.8.0 - Several minor bug fixes