Fixes #2600. Restyles and repositions sidebar tab.
Uses content-wrapper template for video-wrapper view.
Resizes video player correctly. Deletes defunct video-wrapper template.
Enforces alphanumeric sorting by title for in topic tree during content import.
Fixes #2608.
Merge branch 'wch' into content_display
Merge pull request #2644 from rtibbles/content_display

Content display fixes (for WCH)
Merge branch 'wch' into content-fields