Release script: Use realpath() to map to current user home
Release script: Use realpath() to map to current user home

This change enables to run the release scripts on linux boxes in which the user's home is not at /home/username

Author: Enrico Olivelli <eolivelli@apache.org>

Reviewers: Sijie Guo <sijie@apache.org>

This closes #1674 from eolivelli/fix/better-userland-mapping

sijie/bookkeeper,sijie/bookkeeper,sijie/bookkeeper,sijie/bookkeeper,sijie/bookkeeper,apache/bookkeeper,apache/bookkeeper,apache/bookkeeper,sijie/bookkeeper,sijie/bookkeeper,sijie/bookkeeper,apache/bookkeeper,apache/bookkeeper,apache/bookkeeper