kallithea-cli: set ssh_locale when creating .ini file so it doesn't have to be set manually before using ssh

The Python standard library does not seem to provide a simple way to
determine the current locale without calling locale.setlocale() and thus
potentially influencing the rest of the program.

Instead, try to determine the locale based on environment variables present
when 'kallithea-cli config-create' is run, and use it to prepopulate the ini
file.