Added stykliste liste to easily give insight into what items are "kits"

[logicguy1]

(removed our price / cost price, this would normally be available to the end user)

What are the changes about?

Added a stykliste list that shows all the samlevarer that are created in the system, this is useful to quickly find a "Kit item"

Stock values are not included into this list as that would be quite the job to recursively fetch stock values of child items (as a stykliste can include other styklister), this would be great UX for end user however.

The icon i used is just a simple crate icon, i couldn't really think of another way to iconize a stykliste (perhaps a collection of boxes), but if anyone has any good ideas ill gladly update the PR

Have you checked the following?

• I have updated relevant documentation at https://github.com/DANOSOFT/saldi/wiki
• I have checked that i am not linking to any external resources such as external style- or javascript-files, that could compomise stabilaty
• I have read and understood the developer guidelines
  https://docs.google.com/document/d/1GOmomtvKf21OV2VWNOIPweDi4gJHpMCK5qXzrPrypUc/edit?usp=sharing