allow create_package(".") as a special case?

[kevinushey]

For example, if I try to run this inside a folder I just created, I see:

> usethis::create_package(".")
New project 'example' is nested inside an existing project './', which is rarely a good idea.
If this is unexpected, the here package has a function, `here::dr_here()` that reveals why './' is regarded as a project.
Error: User input required, but session is not interactive.
Query: Do you want to create anyway?
Execution halted

The warning message isn't quite accurate, but usethis infers the project as already existing because the .git directory exists (even though that's the only thing in the directory).

A more general reprex from the shell:

cd $(mktemp -d)
mkdir .git
R --vanilla -s -e 'usethis::create_package(".")'

[hadley]

Yeah, that seems like a reasonable idea to me.