Rename package to {cfr}

[pratikunterwegs]

This PR renames the package to {cfr} from {datadelay}, and fixes #47.

This PR also:

1. Adds a package logo with the new name, and fixes Add package logo #53,
2. Updates the pkg maintainer to @pratikunterwegs, and adds @TimTaylor, @joshwlambert, and @Bisaloo as reviewers - could you please say whether you're okay with this.

[Bisaloo]

Could you also please submit PRs to:

• the r-universe repo to update the pkg name and link
• the hex-stickers repo with the logo in png & svg

[Bisaloo]

This folder can contain important files we want to commit. Do you have any issues that lead you to add it here?

[pratikunterwegs]

Currently it only contains the directoy favicon/ with icons of different sizes - should these be committed? I can allow tracking if so.

[pratikunterwegs]

Converting this to an issue for now - can be added to tracking if it becomes necessary, but I don't see a pkgdown directory in our other repos so keeping it out for now.