Update electron to 1.7.12 (#2029)
Fixed: incoming messages sometimes didn't appear at all (#2050)
Fixed: 'Cannot find module ./app/locale' error popup when attempting to start another instance of the app on Windows (#2017)
Fixed: Setting NODE_ENV environment variable to 'development' would point it at staging servers (#2010)
'Restart' -> 'Restart Signal' button in update dialog, thanks @StevenXL (#2024)
Set conversation disappearing messages state and contact block state on initial link (#1980)
Dev: