manpages are wrong about PATH inheriting from the environment now

I posted this on bug #1779767 but since that got closed it's probably going to be lost there.

tl;dr the manpage(s) needs to be fixed for this change as well:

Julian, thanks for the fix. In crontab(5) in cron 3.0pl1-136ubuntu2 the manpage is now wrong. It says:

> Several environment variables are set up automatically by the cron(8) daemon. […] PATH is set to "/usr/bin:/bin". HOME, SHELL, and PATH may be overridden by settings in the crontab […]

and also

> On the Debian GNU/Linux system, cron supports the pam_env module, and loads the environment specified by /etc/environment and /etc/security/pam_env.conf. It also reads locale information from /etc/default/locale. However, the PAM settings do NOT override the settings described above nor any settings in the crontab file itself. Note in particular that if you want a PATH other than "/usr/bin:/bin", you will need to set it in the crontab file.

These should be fixed I think. There might be other spots that I didn't notice yet too.