Color blind-friendly palette for ksrates output plot

[Cecilia-Sensalari]

The default ksrates palette in the config_file.txt is not optimized for color blindness, for example because it features Red and ForestGreen. Even though this file can be customized by the user, the software should provide by default a color blind-friendly palette.

Current palette:

divergence_colors =  Red, MediumBlue, Goldenrod, Crimson, ForestGreen, Gray, SaddleBrown, Black

TODOs:

• Find a palette that contains at least 8 colors and that is compatible with color blindness
• Implement it in the provided configuration files in the test and example datasets
• Implement it in the code when ksrates generates a new empty configuration file
• Update the documentation page showing the configuration file