Release grateful 0.2.10

[Pakillo]

Prepare for release:

• [x] git pull
• [ ] Check current CRAN check results
• [ ] Polish NEWS
• [ ] usethis::use_github_links()
• [ ] urlchecker::url_check()
• [ ] devtools::build_readme()
• [ ] devtools::check(remote = TRUE, manual = TRUE)
• [ ] devtools::check_win_devel()
• [ ] revdepcheck::revdep_check(num_workers = 4)
• [ ] Update cran-comments.md
• [ ] git push

Submit to CRAN:

• [ ] usethis::use_version('patch')
• [ ] devtools::submit_cran()
• [ ] Approve email

Wait for CRAN...

• [ ] Accepted :tada:
• [ ] usethis::use_github_release()
• [ ] usethis::use_dev_version(push = TRUE)