Output page: Fix VMR-9 settings again.

The resize combobox and the D3D fullscreen checkbox were still disabled after 49ae81f0bfe92cc0b9b1aa89c404ceb02e4334cf.
Output page: Add back the DirectShow video renderer tooltip.

Side effect of 22e8eab8c24eee10131a87d4e5550ef07a29f5c2, the unused resource string with the same ID than the control caused the tooltip to be registered automatically.
Fix: Update the chapter marks on the seekbar when the media length changes.

Mostly useful for MKV with multiple editions.

Fixes #3963.
Update translations from Transifex:

 - Greek.