Large request must must be pageinateable

[sjefen6]

Large and possible heavy request should be pageinateable. This will allow server side implementations to return less items and not force it to generate a huge response. Quicker server side responses will in turn make clients faster, and addidtionaly they can start showing the library before all content is synced. The client should be able to set a maximum number of items returned, but the server side implementation can choose to futher limit the amount if items returned without beeing forced to return a fixed amount of items (for example limit items by execution time).

[sjefen6]

I think paginatable results can have an optional input pagetoken. If more pages are available than is returned, then it the result must contain an "nextPageToken", "prevPageToken" or both. Clients can also optionally set "maxResults"