Feat/companies and contactor

[JohanHjelsethStorstad]

WARNING merge after #346 as this branch includes those commits. This PR adds a company system to PN, and uses them in the jobads system. It also does a general refactor:

• Jobads system moved to /career together with companies.
• The career landing page (added) links to companies and jobads as well as company-presentations (bedbress)
• To do this link to company-presentations on events safely a special-event-tag system has been added.
• The /career landing page somewhat adjusts based on if the user is logged in (Karriere) and not (For bedrifter)
• Includes a special CmsLink (new thing) that can be set to point to contactor.no. This special CmsLink will soon be useful on front-page and in nav-bar.
• Makes the Date component from #346 better by clearly stating that we are talking about UTC on initial render
• Changes the expiration date atr. on api-keys to also follow UTC convention in database and backend
• Modifies the component so it displays local date to user while sending UTC to the backend. The local can be accessed still on [name]-local input name if it is ever needed.

The general idea behind /career is to in the future expand it to integrate with contactor.

[JohanHjelsethStorstad]

Oh and it also adds functionality to actually archive jobads hehe

[JohanHjelsethStorstad]

With this PR I belive the JobAd system is ready for release