Removed the ability to add Discussion and advanced components to Content Libraries.
Merge pull request #6177 from open-craft/content_libraries/12-remove-discussion

Remove Discussion and Advanced Components Interface From Libraries (SOL-120) (WIP)
Paging for LibraryView added with JS tests.
Added tests for Library pagination.
Addressed notes from reviewers on Library Pagination.
Factored out Pagination into its own Container view.
Addressed further review notes for Library Pagination