Submission notes

RESUBMISSION: Fixed a test that failed on the pre-v4 R because of stringsAsFactors differences.

Purpose

Fixes some issues related to the development release of R 4.0 that sets stringsAsFactors = FALSE by default, that were showing up as errors on the CRAN checks (Debian, Fedora, and Solaris platforms).
Fixes some minor bugs discovered following the milestone v2.0.0 release.
Moves two data objects to another package, reducing the size of the package.

Test environments

local macOS 10.15.3, R 3.6.3
ubuntu Ubuntu 18.04 LTS and 18.10, R 3.6.3
Windows release via devtools::check_win_release()
Windows devel via devtools::check_win_devel()
rhub::check_on_debian()
rhub::check_on_solaris()

R CMD check results

No ERRORs, NOTEs, or WARNINGs produced.

Downstream dependencies

This release causes no new breaks in other packages.