Custom nvm_dir does not work in protected directories like /opt/nvm out of the box

[morgangraphics]

As described in #26 there is a bug where declaring a custom nvm directory location does not work properly out of the box. This is a permissions issues related to the user running the playbook and associations with group(s) or being added to the sudoers file. A temporary workaround is to assign the directory to the specific user until we address things properly with #26.