2d471636eb wallet: Remove trailing separators from -walletdir arg (Pierre Rochard)
ea3009ee94 wallet: Add walletdir arg unit tests (Pierre Rochard)
Pull request description:
If a user passes in a path with a trailing separator as the `walletdir`, multiple BerkeleyEnvironments may be created in the same directory which can lead to data corruption.
Discovered while reviewing https://github.com/bitcoin/bitcoin/pull/12493#issuecomment-417147646
Tree-SHA512: f2bbf1749d904fd3f326b88f2ead58c8386034355910906d7faea155d518642e9cd4ceb3cae272f2d9d8feb61f126523e1c97502799d24e4315bb53e49fd7c09