It's obsolete anyway.

It's obsolete as we are not going to implement raft_applier fiber
anymore.

Use direct structure names instead of aliases
for better IDE code surfing

1

add roadmap-en

Tell a story.

It's already called `raft_conf_change_loop` in code.

Extend documentation with raft log processing algorithm.

Describe `conf_change_loop` and graceful shutdown logic.

Bring the algorithm description in accordance with actual
implementation. Also provide some comments to the code.