[WIP] Add zap2epg TV grabber to tvheadend

[th0ma7]

Motivation: TVH lacks of built-in TV grabber as the XMLTV project is pretty much all using perl with target compiled CPAN modules making cross-build not sustainable with the framework. Changes in this PR incorporate zap2epg python EPG grabber directly to TVH. This allows using built-in routine tasks from TVH without needing additional cron jobs.
Linked issues: Superseeds previous zap2it standalone package #4608 and include requests python wheels which closes #4678

Checklist

• Build rule all-supported completed successfully
• Package upgrade completed successfully
• New installation of package completed successfully

Notes

• Currently pending the merge upstream of Python3 th0ma7 updates edit4ever/script.module.zap2epg#37

[th0ma7]

@hgy59 I thought it was that easy of adding a WHEELS section to the spk to get the python requests library to work.

I'm still getting ModuleNotFoundError: No module named 'requests'.
Installer log file is relatively useless:

# cat tvheadend_install.log 
Tue Jun 15 16:27:47 EDT 2021
===> Step preuninst. USER=tvheadend GROUP=sc-media SHARE_PATH=
Tue Jun 15 16:27:51 EDT 2021
===> Step postuninst. USER=tvheadend GROUP=sc-media SHARE_PATH=

Advices/pointers to solve this would be much appreciated...
(now thinking, does it install python wheels only at install time or also during upgrades?)

[hgy59]

please update some outdated files.

[th0ma7]

PR pending merge of edit4ever/script.module.zap2epg#37 to confirm download URL.

[th0ma7]

please update some outdated files.

Thnx for the review @hgy59, much appreciated. As mentionned some of the changes requested are already present in PR #4545.

[hgy59]

leftover

[hgy59]

replace zap2it by zap2epg

[hgy59]

sorry my latest review is too late...

[th0ma7]

sorry my latest review is too late...

@hgy59 never too late! I'll port it over to #4686