Enable unrotated axis ticks

[numeredev]

DESCRIPTION

What does your feature request improve on? Please describe.
According to some research, rotated axis ticks are much harder to read than rotated ones. Would appreciate, if there's an option to unrotate them as well as a setting to change the default behavior.

Describe the solution you'd like
Create an option tickrotate/notickrotate and a corresponding setting to change its default value.

Additional context
Add any other context or screenshots about the feature request here.

(Do not write below this line)

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DEVS' SECTION

ANALYSIS

Depending on the result of the "U" option of the axis, this can be solved with that. If possible, there can be a corresponding option for that. If the "U" option does not resolve the issue, we won't fix the problem for now.

IMPLEMENTATION STEPS

(see also our Wiki for implementation guidelines)

• Implement the necessary changes in a new branch created here on GitHub
• Test your implementation

DOCUMENTATION STEPS

(see also our Wiki for further information)

• Update the changes log
• Add comments to your implementation
• Add Doxygen documentation comments
• Create or update the documentation articles (*.NHLP and *.NDB files, if needed)
• Update the language strings (*.NLNG files, if needed)

PULL REQUEST

• Create a pull request for your changes
• Fill out the template
• Assign @numere-org/maintainers as reviewers

[numeredev]

De-prioritized due to printing problems with the axis labels. Needs some manual tweaking.