Modernize and clean up k4run

[jmcarcell]

Fixes #241 and does a much needed clean up of the script.

BEGINRELEASENOTES

• Add a docstring for the function that adds the arguments
• Remove dead code, obvious comments and global variables
• Use f-strings
• Fix arguments when a property is a std::vector. Related to this fix now k4run will also display properties for which the default value is an empty list, previously these were not displayed.
• Improve formatting of the message with all the values of all the properties

ENDRELEASENOTES

Now the messages at startup with all the options are cleaner. Before:

[k4run] Option name: Transformer.OutputLevel Transformer.OutputLevel 0
[k4run] Option name: Transformer.Asynchronous Transformer.Asynchronous False
[k4run] Option name: Transformer.InputCollection Transformer.InputCollection ['MCParticles']
[k4run] Option name: Transformer.OutputCollection Transformer.OutputCollection ['NewMCParticles']
[k4run] Option name: Transformer.Offset Transformer.Offset 10

after:

[k4run] Option name: Transformer.OutputLevel 0
[k4run] Option name: Transformer.Asynchronous False
[k4run] Option name: Transformer.InputCollection ['MCParticles']
[k4run] Option name: Transformer.OutputCollection ['NewMCParticles']
[k4run] Option name: Transformer.Offset 10

[jmcarcell]

If there aren't any other comments or complains I'll merge this soon since I want this fix to be included in the next tag that is coming soon.