v2.0-3

User-visible changes

• Per #33, remove as.matrix.igraph() as it has been moved to igraph. Adjust the tests accordingly.
• Fix netcompare() and compareAttributes() (#34 and #35).

Internals

• Fixed #21, #28 related to data frame vs tibble differences.
• Update tests to use testthat.
• Use covr for test coverage.
• Change email address to Gmail and add ORCID to DESCRIPTION.
• Resave data using usethis::use_data().
• Refactor tests of attrmap(), asIgraph() and asNetwork() (#34)