Detect and create default licence

[maelle]

Cf r-lib/usethis#482

[ha0ye]

I was just wondering about this myself... it definitely caused me a bit of confusion that I set up my defaults following the help for use_description(), and this would be reflected in DESCRIPTION, but without any license files created...

[maelle]

You mean in usethis or starters?

FWIW we, well at least I am no longer working on starters. Cc @stephlocke

[ha0ye]

🤷‍♂ It looks like the issue was closed in usethis.
Admittedly this is fairly low priority!

[stephlocke]

By default in create_package_project we create an MIT license. For analysis and basic projects, we don't set any license because typically these need a more bespoke handling.

At the mo, we don't really support any passing of defaults into the DESCRIPTION file so it's not especially relevant to include a license requirement in it.

This isn't to say we can't do more on licensing or smart defaults, just that right now the opinionated setup is MIT by default for packages, and Bring Your Own License for everything else.