The comments for the require package were just copied over
from the assert package when generating the functions.
This could lead to confusion because
1. The code-examples were showing examples using the
assert package instead of the require package
2. The function-documentation was not mentioning that
the functions were calling `t.FailNow()` which is some
critical information when using this package.

Co-authored-by: Olivier Mengué <dolmen@cpan.org>

…ire-package