Ignore TLS failures, conditionally.

[skx]

This would close #113, if it were tested and confirmed by @StayPirate.

[StayPirate]

It doesn't work for me. I hope I've tested it correctly.

Here is my testing feeds.txt:

/app # cat /root/.rss2email/feeds.txt
https://gitlab.suse.de/security/secbox-image.atom
- template: /templates/default.tmpl
- insecure

Here are the steps I took to build and test the image:

> git clone https://github.com/skx/rss2email.git
> cd rss2email
> git switch 113-insecure
> podman build -t r2e:test .
> podman run --rm -ti --env-file=./.env -v ./a:/root/.rss2email/feeds.txt --name test r2e:test sh
container > ./rss2email cron --verbose ******@protonmail.com
Fetching feed: https://gitlab.suse.de/security/secbox-image.atom
error processing https://gitlab.suse.de/security/secbox-image.atom - Get "https://gitlab.suse.de/security/secbox-image.atom": tls: failed to verify certificate: x509: certificate signed by unknown authority

[StayPirate]

Now that I read the description of the new option carefully I realized that I have to set the option to either true or yes.

And it works with the following feeds.txt config:

https://gitlab.suse.de/security/secbox-image.atom
- template: /templates/default.tmpl
- insecure: true

[StayPirate]

Nice.

/app # ./rss2email cron --verbose ********@protonmail.com
error with config-file /root/.rss2email/feeds.txt - options should be of the form 'key:value', bogus entry found ' insecure', beneath feed https://gitlab.suse.de/security/secbox-image.atom
/app #