Update git submodules
- Update extensions/CategoryTree from branch 'REL1_39' to 023719dadd65652e2147c3b0f209c7ea63acc666
- Localisation updates from https://translatewiki.net.
Change-Id: I4159b610f6aed9fea3f7f83f6fba1bdb816b4525
- Localisation updates from https://translatewiki.net.