[FEATURE]: Add check and diff to user module

[nikolisg7]

Describe the solution you'd like
Support for check_mode and diff reports in the user module

Describe alternatives you've considered
None

Additional context
Since working with user settings and creation on storage systems is a tricky business, it would best to be able to exploit the check and diff features of Ansible to do dry runs before final deployment. Most of the newer powerscale ansible modules now support these features. Thanks!