minor #4644 Docs: add info about "-vv..." (voku)

This PR was submitted for the master branch but it was merged into the 2.15 branch instead (closes #4644).

Discussion
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Docs: add info about "-vv..."

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Commits
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2d7c0ee Docs: add info about \"-vv...\"

README.rst

@@ -166,9 +166,17 @@ NOTE: the output for the following formats are generated in accordance with XML
 * ``junit`` follows the `JUnit xml schema from Jenkins </doc/junit-10.xsd>`_
 * ``checkstyle`` follows the common `"checkstyle" xml schema </doc/checkstyle.xsd>`_
 
+The ``--quiet`` Do not output any message.
 
 The ``--verbose`` option will show the applied rules. When using the ``txt`` format it will also display progress notifications.
 
+NOTE: if there is an error like "errors reported during linting after fixing", you can use this to be even more verbose for debugging purpose
+
+* ``--verbose=0`` or no option: normal
+* ``--verbose``, ``--verbose=1``, ``-v``: verbose
+* ``--verbose=2``, ``-vv``: very verbose
+* ``--verbose=3``, ``-vvv``: debug
+
 The ``--rules`` option limits the rules to apply to the
 project:
 

src/Console/Command/HelpCommand.php

@@ -71,9 +71,17 @@ public static function getHelpCopy()
 * ``junit`` follows the `JUnit xml schema from Jenkins </doc/junit-10.xsd>`_
 * ``checkstyle`` follows the common `"checkstyle" xml schema </doc/checkstyle.xsd>`_
 
+The <comment>--quiet</comment> Do not output any message.
 
 The <comment>--verbose</comment> option will show the applied rules. When using the ``txt`` format it will also display progress notifications.
 
+NOTE: if there is an error like "errors reported during linting after fixing", you can use this to be even more verbose for debugging purpose
+
+* ``--verbose=0`` or no option: normal
+* ``--verbose``, ``--verbose=1``, ``-v``: verbose
+* ``--verbose=2``, ``-vv``: very verbose
+* ``--verbose=3``, ``-vvv``: debug
+
 The <comment>--rules</comment> option limits the rules to apply to the
 project: