Investigate and support extra features

There are still many features in raft-rs that we haven't been able to use yet due to limited time.
Let's directly use these features and verify if they work as intended.
Ideally, it would be great to write some test codes that they function properly through test code.

If the feature cannot be enabled solely by changing options, please submit new issues.
(*This list can be updated.)

- [ ] prevote algorithm
- [ ] commit group
- [ ] election priority in vote