[Feature] Add an activity

[sthewissen]

What?

• [x] User should get a wizard style screen answering the questions.
  • [x] Activity type
  • [x] Technology area
  • [x] Max 2 additional Technology area
  • [x] Title
  • [x] Date
  • [x] Description
  • [x] URL
  • [x] Visibility
  • [x] Quantity fields (these are fixed, but with dynamic labels)
• [x] A next and previous button lets the user navigate the wizard.
• [x] Required fields are validated.
• [x] Add indicators for loading and saving.

[sthewissen]

Basics for this are in place, there are a few nice to have QoL improvements to make though:

• Add a search
• Show most recent chosen type or a popular type you choose a lot

This goes for picking technologies and activity types. Also still lacking is validation.