Compatibility with igraph 2.0.0

[krlmlr]

@jefferis @jdmanton @mmc46 @dmurdoch: This package fails its checks for the release candidate for igraph 2.0.0. See https://github.com/igraph/rigraph/blob/igraph-0.10/revdep/problems.md for details.

Is this a problem in your package? Should we be doing things differently?

Install the 2.0.0 release candidate using pak::pak("igraph/[email protected]") .

We're planning to release igraph 2.0.0 just before CRAN's closing on Christmas. This should give us at least until mid-January to resolve this and keep CRAN happy at the same time. Thank you for your help!

Tracker: https://github.com/igraph/rigraph/issues/989.