IssueTracker

Currently when users enable placeholders in PagingConfig, Paging does not check whether itemsBefore and itemsAfter is implemented.

If users did not override LoadResult.page.itemsBefore/itemsAfter's default value Int.MIN_VALUE with their own implementation, users would see wrong jumping behavior.

Ideally we want to check for and log that discrepancy. Also, add documentation defining the relationship between PagingConfig.enablePlaceholders and itemsBefore/itemsAfter.