Create Asset Groups - Backend

[Grand666]

Based on a search, it should be possible to select multiple assets and create an "Asset Group". You will later on be able to view this group, add and remove assets from the group. (You need at least Read Role to the assets)

When viewing the group, you should be able to do both Bulk Update and single updates to Assets Metadata. (Given you have write access to the assets)

1. Create Group
2. Remove Group
3. Update Group
4. List Groups

Acceptance Criteria

• [x] You're able to create Asset groups
• [x] You can add and remove assets from the group
• [x] Tested locally
• [x] Create Unit tests
• [x] Create Integration tests in the Test Suite

[Nicolas-Northtech]

Main functionality is working and tested, I need a little bit more of information about read/write access before I can definitely finish it.