Update git submodules
- Update skins/MonoBook from branch 'REL1_39' to 0d8efc9532336bf3681fd382965c6970c86c0f09
- Localisation updates from https://translatewiki.net.
Change-Id: Id51288777d9745b9aef7e441e0a7fa760373b049
- Localisation updates from https://translatewiki.net.