Feature/merge 3 0 develop (#298)

* merging 3.0 into develop

* N°5102 - Allow to send emails (eg. notifications) using GSuite SMTP and OAuth
* migration to iTop 3.1

Co-authored-by: Eric Espie <eric.espie@combodo.com>

lib/league/oauth2-google/phpunit.xml.dist

@@ -0,0 +1,28 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<phpunit backupGlobals="false"
+         backupStaticAttributes="false"
+         bootstrap="vendor/autoload.php"
+         colors="true"
+         convertErrorsToExceptions="true"
+         convertNoticesToExceptions="true"
+         convertWarningsToExceptions="true"
+         processIsolation="false"
+         stopOnFailure="false"
+         syntaxCheck="false"
+>
+    <testsuites>
+        <testsuite name="all">
+            <directory>./test</directory>
+        </testsuite>
+    </testsuites>
+    <filter>
+        <whitelist>
+            <directory suffix=".php">src/</directory>
+        </whitelist>
+    </filter>
+    <logging>
+        <log type="coverage-text" target="php://stdout"/>
+        <log type="coverage-clover" target="build/logs/clover.xml"/>
+        <log type="coverage-html" target="build/coverage" charset="UTF-8" yui="true" highlight="true"/>
+    </logging>
+</phpunit>