Implement presentation of instances in signing task in messagebox

[tba76]

Description

Considerations

• Do we need to define element.RoleRequirement for the reporteeElemen to get the correct status?
  Yes - in storage we must check if user has rights to sign or just to read. Based on this a new propert(y/ies) should be included in the messageboxInstance class.

Additional Information

Tasks

• Add signing as an action to the multidecision request for filtering msgbox instances
• extend messagebox instance and instance event type models
  • push new storage.interface
• Implement required logic to handle signing when authorizing instances
• Implement required logic to handle retrieval of signing related instance events
  • test in SBL
• Confirm the name of the task to ensure that element is placed correctly in msgbox
• implement required changes in sbl for reportee element list and activity log
• QA
• manual test

Acceptance Criterias

• Activity log displays events of Signed and Sent to signing
• Button should say "Gå til skjema" when element in sign task is expanded
• Element you can read but not sign should say "Venter på andre"
• Element you can sign should say "Til signering;"
• Elements sorted based on date alongside elements in data task