doc:it_IT: translation of documents in process/

Translations for the following documents in process/:
    - email-clients
    - management-style
Signed-off-by: Alessia Mantegazza <amantegazza@vaga.pv.it>
Signed-off-by: Federico Vaga <federico.vaga@vaga.pv.it>
Link: https://lore.kernel.org/r/20200413163457.52669-1-federico.vaga@vaga.pv.itSigned-off-by: Jonathan Corbet <corbet@lwn.net>