Release notes 0.20.12

Bitcoin ABC version 0.20.12 is now available from:

https://download.bitcoinabc.org/0.20.12/

This release includes the following features and fixes: - The unloadwallet RPC is now synchronous, meaning that it blocks until the wallet is fully unloaded. - Fixed a bug where wallet handles were not being freed correctly, effectively causing a memory leak when many wallets were called via loadwallet and unloadwallet. - Better error reporting for parsing errors in configuration files.