chore!: deprecation of scale param of eigen_centrality()

[maelle]

Fix #1353

But waiting on feedback there.

I also used this as an opportunity to align test files with scripts, but in separate commits. 😇

[aviator-app]

Current Aviator status

Aviator will automatically update this comment as the status of the PR changes.
Comment /aviator refresh to force Aviator to re-examine your PR (or learn about other /aviator commands).

This PR was closed without merging. If you still want to merge this PR, re-open it.

---

See the real-time status of this PR on the Aviator webapp.

Use the Aviator Chrome Extension to see the status of your PR within GitHub.

[szhorvat]

To clarify, what will happen is that this parameter will be removed in C/igraph 1.0, and the function will always behave like scale=T.

A more friendly way to deal with this in R is a multi-stage deprecation:

• In the next R/igraph version based on C/igraph 0.10, people who use scale=F should get a warning, but people who use scale=T shouldn't.
• In the first R/igraph version based on C/igraph 1.0, people who use scale=F should get an error. People who use scale=T should get a warning.
• In a subsequent version, scale should be removed entirely.

Maybe this is difficult and not worth the time, so it also works that any explicit use of scale should get a warning right away, and in the first R/igraph based on C/igraph 1.0, we remove scale entirely. This second option is what you seem to be going with, which is probably the best choice (saves us time).

I just wanted to be explicit about the options. I leave the choice to you :-)