doc:it_IT: align Italian documentation

Translation for the following patches

commit 0aa78b105f57 ("Documentation/changes: Raise minimum supported binutils version to 2.23")
commit 7d7178873560 ("Documentation: include sign off for reverts")
commit 905705a8fd43 ("docs: programming-languages: refresh blurb on clang support")
commit 5ff4aa70bf34 ("docs: submitting-patches: use :doc: for references")
commit 030f066f677f ("docs: submitting-patches: describe preserving review/test tags")
commit 68e4cd17e218 ("docs: deprecated.rst: Add zero-length and one-element arrays")
commit 5429ef62bcf3 ("compiler/gcc: Raise minimum GCC version for kernel builds to 4.8")
commit 5b5bbb8cc51b ("docs: process: Add an example for creating a fixes tag")
commit 858e6845654d ("docs: dt: convert submitting-patches.txt to ReST format")
commit cca73e4946c4 ("docs: Correct the release date of 5.2 stable")
commit c170f2eb9648 ("docs: Document cross-referencing between documentation pages")
commit 7c8b9e3000f8 ("kernel-doc: Update "cross-referencing from rST" section to use automarkup")
commit 27def953b63b ("docs: deprecated.rst: Expand str*cpy() replacement notes")
commit 17dca0502314 ("docs: deprecated.rst: Update zero-length/one-element arrays section")
commit 3519c4d6e08e ("Documentation: add minimum clang/llvm version")
commit 0bddd227f3dc ("Documentation: update for gcc 4.9 requirement")
commit 9f364b605f34 ("submitting-patches.rst: presume git will be used")
commit 4ebdf7be21d6 ("Documentation/maintainer: rehome sign-off process")
commit 7433ff33e8ba ("Documentation/process: expand plain-text advice")
commit eb45fb2fb16d ("docs: process: Add cross-link to security-bugs")
commit bdc48fa11e46 ("checkpatch/coding-style: deprecate 80-column warning")
commit f67281a72b30 ("Documentation: process: step 2: Link to email list fixed")

Signed-off-by: Federico Vaga <federico.vaga@vaga.pv.it>
Link: https://lore.kernel.org/r/20201114083342.13935-1-federico.vaga@vaga.pv.it
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
diff --git a/Documentation/translations/it_IT/process/email-clients.rst b/Documentation/translations/it_IT/process/email-clients.rst
index 66d3d65..de7d32f 100644
--- a/Documentation/translations/it_IT/process/email-clients.rst
+++ b/Documentation/translations/it_IT/process/email-clients.rst
@@ -32,6 +32,11 @@
 ben apprezzati perché rende più difficile citare porzioni di patch durante il
 processo di revisione.
 
+Inoltre, è vivamente raccomandato l'uso di puro testo nel corpo del
+messaggio, sia per la patch che per qualsiasi altro messaggio. Il sito
+https://useplaintext.email/ può esservi d'aiuto per configurare il
+vostro programma di posta elettronica.
+
 I programmi di posta elettronica che vengono usati per inviare le patch per il
 kernel Linux dovrebbero inviarle senza alterazioni.  Per esempio, non
 dovrebbero modificare o rimuovere tabulazioni o spazi, nemmeno all'inizio o