Provide a Docker image with installed CodePolicy.

[svenoe]

@bschmalhofer's suggestions for this are:

• No longer package Perl::Tidy in Kernel/cpan-lib, (remove Kernel/cpan-lib from @inc)
• Provide a cpanfile for local installations of CodePolicy
• Add the feature 'devel:codepolicy' in bin/otobo.CheckModules.pl for OTOBO 10.0.8
• Include 'devel:codepolicy' either in the OTOBO Docker image or in a dedicated container

In my opinion these are still two different things. The question whether we should get rid of Kernel/cpan-lib should be answered for OTOBO and CodePolicy together. Going two different routes is not optimal, I think. From my standpoint, if you use docker, where all this stuff is done automatically, providing a cpan-file is definitely the nicer option. For standard installs however, where some people want to use the system package manager for their perl libraries, I still think, we should just keep the cpan-lib for packages where we want specific versions. (I also see the point though, that in general it would be nice to have a fix "tested" version of every cpan package for every OTOBO release, which could much more easily be provided via cpan... But this is a discussion, which really is more important for OTOBO itself, compared to CodePolicy.)

Secondly, I agree that it would be nice to provide a devel version of otobo-docker, which automatically includes CodePolicy, Fred, Selenium, and possibly other tools. (The reemergence of dbviewer? ;) )

Originally posted by @svenoe in #3 (comment)

[bschmalhofer]

Somewhat related to the requests above, it would be nice to be able the CodePolicy just like a regular Perl package. This avoids the need to remember where the CodePolicy sandbox is located.
The only thing needed is a sane Makefile.PL or Build.PL. Maybe also move the included version of Perl::Tidy to a more standard location.

[bschmalhofer]

Let's concentrate on the Docker image aspect for this issue.

The question on whether Perl::Tidy should be bundled with CodePolicy has already been discussed between @svenoe and @bschmalhofer . The decision was to keep a fixed version bundled.

The issue whether to provide a cpanfile is more related to #56.

[bschmalhofer]

Here is another idea. When looking at https://github.com/RotherOSS/otobo/runs/3684898399?check_suite_focus=true we see that there is one step that takes most of the time. That's installing the CPAN dependencies from cpanfile.docker. This could be eliminated by using a dedicated Docker image with all the dependencies installed. A better idea might be to simply cache the CPAN dependencies. Either the directory with the installed Perl modules, or the .cpanm workdir.