Re-Formatted and re-organized POMs - Part 2

[hypfvieh]

This is a follow-up to #446.

I merged the latest upstream changes and revisited the POM configuration:

• Moved more dependencies to dependency management
• Removed broken shade-plugin config in library (that`s the root cause for broken POMs)
• Added javadoc and maven-source-plugin to core module, so all submodules will create sources and javadoc jars
• Javadoc Plugin is disabled by default and will be enabled by release profile (automatically enabled by maven-release-plugin when release:prepare release:perform is called)

I tested this configuration by changing the groupId and Maven Central stuff to my personal groupId etc. For testing I disabled the nexus-staging-maven-plugin and disabled the broken unit tests of #478. I then checked the uploaded artifacts in Maven Central Nexus manually.
All release checks of Nexus are passed now.

• Javadoc JAR ✔️
• Source JAR ✔️
• Test JAR ✔️
• All JARs signed ✔️

Something more I've noticed:
The unit tests are really old school designed. It relies on jupiter-vintage which is a compatibility layer to allow old Junit 3 and 4 style tests to be used.
These days the tests should really be JUnit 5 native tests using proper annotations, not extending "TestCase" and not using "TestSuite".

JUnit 5 offers a lot of improvements e.g. using @ParametrizedTest, custom test names, running tests concurrently etc.
As testing is a big topic itself, I did not change anything here, but I would highly recommend think about refactoring those tests (to also get rid of forced alphabetically execution).

And one last note:
This PR includes the broken unit tests I reported in #478.
This means, this PR will not solve that issue and will only work when the unit tests are fixed.

[jstaerk]

@hypfvieh are you available tomorrow afternoon e.g. ~15°°? I would try another merge but I may need support if it doesnt work.

[hypfvieh]

We can try it. Usually I'm at work till 4 pm, but you can try to contact me by email (address should be in the commit).

[jstaerk]

Hi,
I didnt see the email and I'm no longer sure if this will be released today, tomorrow, sunday or maybe monday but please contact me at jochen at zugferd.org