Update git submodules
- Update extensions/Math from branch 'REL1_40' to 5efea78ebaa2f585948303201534a09307dc8ec1
- Localisation updates from https://translatewiki.net.
Change-Id: Icb51a1977f3295bd405952ee43a848dcc3972127
- Localisation updates from https://translatewiki.net.