Update zeal ppa for Ubuntu

[cmorty]

I'd love to see an updated PPA (https://launchpad.net/~zeal-developers/+archive/ubuntu/ppa). I'll support you, if I can. I already packed some stuff - although that was about 10 years ago (https://launchpad.net/~morty).

[trollixx]

@cmorty PPA indeed needs to be updated, if you are interested in maintaining it, that'd be great. You can find the old metadata in the zeal-packaging repo. Ideally there should be a way to make GitHub actions trigger deployment to PPA when metadata is updated.

[cmorty]

@trollixx I can at least commit to getting the ppa up and running again. I'll see what I can do about the "build on meta-data-change". At the time we always had an extra branch we merged into.

[novaTopFlex]

I believe that Zeal is now in the default repository listings for recent versions of Ubuntu Linux. Therefore, alternative Zeal packaging is not necessary. However, I also believe that the re-institution of the Personal Package Archive is absolutely necessary in the best effort of ensuring bug- and potential security-fixes to the Zeal documentation browser.

[rwperrott]

A access failure at https://code.launchpad.net/~zeal-developers/zeal/github-ubuntu, maybe because still using obsolete github username/password login method, rather than a valid github classic token with enough permissions, which I think can be hacked as a username or a password on legacy systems. This got me about a year ago for another well known automated build system, still only providing username and password login method for github!

Import details
Import Status: Failed

This branch is an import of the HEAD branch of the Git repository at https://github.com/zealdocs/zeal-ubuntu.git.
The import has been suspended because it failed 5 or more times in succession.

Last successful import was on 2016-01-25.
[Failure] Import started on 2016-01-29 on [pear](https://code.launchpad.net/+code-imports/+machines/pear) and finished on 2016-01-29 taking 15 seconds — see the log
[Failure] Import started on 2016-01-27 on [pear](https://code.launchpad.net/+code-imports/+machines/pear) and finished on 2016-01-27 taking 10 seconds — see the log
[Failure] Import started on 2016-01-26 on [russkaya](https://code.launchpad.net/+code-imports/+machines/russkaya) and finished on 2016-01-26 taking 25 seconds — see the log
[Failure] Import started on 2016-01-26 on [russkaya](https://code.launchpad.net/+code-imports/+machines/russkaya) and finished on 2016-01-26 taking 30 seconds — see the log

Also, where is recent Ubuntu build, like for jammy?