nvda

e9cfa1b1 - Ensure pickle files can be read by earlier versions of NVDA (#7105) (#10255)

Ensure pickle files can be read by earlier versions of NVDA (#7105) (#10255) Impacts both the add-ons state and the updater state files. Both are now written using pickle protocol 0 so that Python 2 version of NVDA can read them in case of downgrading. Re https://github.com/nvaccess/nvda/pull/10224#issuecomment-533459119