aide::cron: Add max_mail_lines feature.

[olifre]

This allows to limit the maximum number of lines sent in change mails before the mail is truncated. By default, no truncation happens.

This functionality is useful to prevent too large mails when OS updates happen, which may be bounced by mail servers otherwise.

[kekogya]

@olifre First off, thank you for your contribution. There appears to be some conflicts due to a pull request and changes that are in master. Could you please please re-base your pull request with the updated master? Also, for the head command, isn't it supposed to have a space after the -n? The code I am referencing are below:

${head_path} -n${max_mail_lines}
${_head_filter}${mail_path}

[olifre]

There appears to be some conflicts due to a pull request and changes that are in master. Could you please please re-base your pull request with the updated master?

Sure, I saw the recent additions only now — PR updated 😄 .

Also, for the head command, isn't it supposed to have a space after the -n?

In fact, both are accepted by head, but you are correct that adding the space is likely more standard conforming in case there is another head implementation out there. I've added the space and force-pushed 😉.

[kekogya]

@olifre thank you for getting the branch PR updated. I will work on publishing an updated module to the forge in the next couple of days.