When performing a factory reset, we don't want to wipe all keychain
entries. The only keychain entry should be the vault's passphrase,
and we need this to be able to decrypt the vault at next startup
(to avoid it being reported as corrupt).
This change ensures persistent data is stored in XDG_DATA_HOME
instead of XDG_CACHE_HOME on linux.
It adds the UserData() method on locations.Provider to return a path
suitable for storing persistent data. On linux, this returns
$XDG_DATA_HOME/protonmail (likely ~/.local/share/protonmail), and on
non-linux this returns os.UserConfigDir() because that is assumed
to be a more persistent location than os.UserCacheDir().
locations.Locations has been modified to use this new data directory;
gluon and logs are now stored here.
* Renaming GUI, CLI, no-impact config.
* License header and documentation rebranding.
* Rename app title and vendor. Impact: manual install
* Migrating mac keychain and launch on startup.
* Fix linter and linter renaming
