clean up staking docs, remove EraElectionStatus references

[kianenigma]

reported by an external user, don't recall their name but kudos to them for pointing out.

I also got rid of some of the superfluous weight comments. With #9090 we can remove almost all of them, actually.

[gui1117]

2 nitpicks but good otherwise

[emostov]

I also got rid of some of the superfluous weight comments.

In general, can we do this with all extrinsics? I think I remember Shawn mentioning these are deprecated with our current benchmarking stack

[shawntabrizi]

I also got rid of some of the superfluous weight comments.

In general, can we do this with all extrinsics? I think I remember Shawn mentioning these are deprecated with our current benchmarking stack

Yeah once we have the storage info comments, all the other benchmarking comments could basically go away. However, it is still nice to keep information about the time complexity of a function, so when users modify code, they know what level of complexity they are working with, and dont change those assumptions.

All functions should basically be linear.