Attractive project readme file

[adineh]

Reference to a related issue in the repository
#27

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Making the project reamde file more attractive in promotions.

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What is this change? improving the project readme file.
What does it fix? the content and structure of the project readme file.
Is this a bugfix or a feature? Just enhancement of the readme file
Does it break any existing functionality or force me to update to a new version? no
How has it been tested? by markdownlint

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• My suggestion follows the governance rules.
• All commits of this PR are signed.
  • I found this requirement on pull request.
• My changes generate no errors when passing CI tests.
• I updated all documentation (readmes incl. figures) according to my changes.
• I have successfully implemented and tested my fix/feature locally.
• Appropriate reviewer(s) are assigned.

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[jdsika]

@ClemensLinnhoff do you know why the linter is complaining even if the links are clickable?

[ClemensLinnhoff]

@ClemensLinnhoff do you know why the linter is complaining even if the links are clickable?

The linter seems to be confused, because the heading is also a link. It does not fail at the link to ## SL1 - Perception Sensor Models but it fails at the link to #### [sl-1-0-sensor-model-repository-template](https://github.com/openMSL/sl-1-0-sensor-model-repository-template).

I guess this is not really a proper heading style. I originally thought the reason is, that the heading is also part of a list (which I wouldn't do) but I tested it and the linter still fails.

There are now three possibilities on how to proceed:

1. Ignore the linter warnings and merge anyways.
2. Add MD051 to a list of Markdown rules to be ignored. (I wouldn't do that, because it is actually a good check)
3. Not use links in headings.

Since linking from the table of contents to the heading works and I think it is kind of intuitive, that the heading directly links to the corresponding repository, I would suggest we choose option 1 and simply ignore the linter warnings.

All that aside, I would still not use a list for the headings. Therefore, I left my commit testing this on SL1-0 in the PR.

[ClemensLinnhoff]

Furthermore, I would not put the images from the repository in the profile, since it makes it quite long to scroll through.

[adineh]

@ClemensLinnhoff: Due to your review comments, following changes has been done in last commit:
- Links removed from Headings
- Headings are no longer parts of lists
- Some white spaces and empty lines removed
- Images has been removed

[ClemensLinnhoff]

@jdsika and I just created a brand new documentation page for OpenMSL: https://openmsl.github.io/doc/

I think we can integrate some of your improvements intended for the profile there. But we can discuss this in the next maintainer meeting.

[ClemensLinnhoff]

I think we can close this PR and the corresponding issue as some of the proposed changes were implemented in the documentation instead of the profile.