#1562: update dokumentation regarding environmental variables

[lubska]

This PR fixes #1562

Implemented changes:

update dokumentation regarding environmental variables:
updates Variables table in Documentation
adds new variables to the table
adds link to an Interface that defines all the available variables

Checklist for this PR

Make sure everything is checked before merging this PR. For further info please also see
our DoD.

• When running mvn clean test locally all tests pass and build is successful
• PR title is of the form #«issue-id»: «brief summary» (e.g. #921: fixed setup.bat). If no issue ID exists, title only.
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[CLAassistant]

All committers have signed the CLA.

[coveralls]

Pull Request Test Coverage Report for Build 21512683408

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 70.456%

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Totals
Change from base Build 21490876384:	0.0%
Covered Lines:	10483
Relevant Lines:	14293

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💛 - Coveralls

[SDallmann]

Were the examples for «TOOL»_VERSION and «TOOL»_EDITION intentionally removed?
Other than that, everything looks good to me 👍

[lubska]

Were the examples for «TOOL»_VERSION and «TOOL»_EDITION intentionally removed? Other than that, everything looks good to me 👍

Thanks for your review! Since these examples cannot contain exact values because they depend on the tool in question , it was decided to leave them empty

[hohwille]

@lubska thanks for your PR. You went through all variables and added example values. 👍
Only after reviewing the documentation I remembered that we provide the default value here (if defined in IdeVariables) or otherwise given an reasonable example with an i.e. prefix.
I added some constructive review comments that you can apply (in diff you as a batch in one commit).
Then we can merge your PR.

[hohwille]

@lubska thanks for the update and conflict resolution. You did all correct 👍
Unfortunately I missed one little detail in my first review.
We can submit/apply that suggestion and then finally merge.