Context:

See parent ticket. We want to add a public API accessible with a user defined access token (same as for export) to import a given collection of previously exported entity definitions (reports and/or dashboard definitions)

Endpoint will be at public/import (post)
and requires a collectionId as parameter as well as an accessToken
Endpoint takes list of exported entities and returns list of newly imported entity Ids

AT:

• users can use a public import API to import entity definitions into a collection
• collectionID and accessToken are required, otherwise API returns error response
• upon import, owner and last modifier are set to "System User"
• import API produces error responses similar to UI import if there are any issues with the import (eg collection to be imported into doesnt exist or doesnt have the required data sources)