[FEATURE]: Add check and diff to user module

**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!