- adds new method (`getUserFromProxyAuth) to server/Auth.js to check for
relevant environment variables and pull the user from the request headers..
- adds `/forwardauth` route to call new proxy auth method
- modified /client/login.vue to call `/forwardauth` and authenticate
the user if returned by forwardauth
- add a helper method in `server/utils/parseBool.js` to help check for
boolean values from environment
- update the readme.md to explain how enable forward auth.
