Improve usage documentation

[sgnn7]

There are various issues with the documentation that should be addressed.

Describe the solution you would like

• [ ] The documentation is solid for IDE use but not for CLI use. Was buildable with VS2019, so maybe that could be updated in the README.
• [ ] The step in USAGE says to use -h in the conjur init command, this did not work in Conjur OSS and I needed to use -u (Conjur v4 leftover?)
• Example very limited
  • [ ] Needs a bit more prod-like usage example
  • [ ] Needs a bit better full-spectrum usage (similar to the demo given)