[worksheet] introduced base classes to handle the settings for error bars centrally

Description

Introduced base classes to handle the settings for error bars centrally.

This centralizes the handling of these properties and is also the preparation work to enable the error bars for bar plots where multiple data sets can be plotted in one single "plot" and we need to be able to specify the different properties for error bars for every data set in the same plot.

Conformity

• Changelog entry
• Unit tests
• Update INSTALL
• Downport
• Fixes:

When external dependencies are removed

• Reporting to ...