FEATURE - Enhancements to the Lever Package

**Are you a Fivetran customer?**

Yes, @martinmalek from Falcon.io

**Is your feature request related to a problem? Please describe.**

No, the customer is scoping out the package and has some good suggestions for building on more to the package.

**Describe the solution you'd like**

The customers [slack](https://getdbt.slack.com/archives/C01D1R2JLLA/p1627306307295400?thread_ts=1626765776.247600&cid=C01D1R2JLLA) thread details their suggestions and requests.

What we want to know the:
- Accumulated time for currently open positions, from requisition open date to current state, resulting in a total open day count per position. This can provide a leaderboard of longest open positions.
- Number of open positions over time per office, department and role type. Seeing historical patterns.
- Funnels for time spent in position lifecycle stages, from requisition, to posting, opportunity states, interviews and hires.
- Identifying where in the process we have choke points.
- Funnels for position counts and % of each stage of the position lifecycle stages, to see where the drop offs occur and how many applicants we converge to hires

We want to to be able to filter on:
- Offices
- Departments
- Role types
- Currently open positions
- Already closed positions
- Hiring Manager
- TA responsible

**Please indicate the level of urgency and business impact of this request**

Customer is scoping this out and has suggestions, most likely not high priority but would be nice additions

**Are you interested in contributing to this package?**

- [ ] Yes, I can do this and open a PR for your review.
- [ ] Possibly, but I'm not quite sure how to do this. I'd be happy to do a live coding session with someone to get this work implemented.
- [X] No, I'd prefer if someone else did this. I don't have the time and/or don't know how to incorporate the changes necessary.