Add a menu entry for copying system information

Which outputs the information from qtdiag, installed plugins,
and general Qt Creator build information.

Task-number: QTCREATORBUG-16135
Change-Id: I618b9883369bae45006bb109f8757e89b091b882
Reviewed-by: David Schulz <david.schulz@qt.io>

src/plugins/coreplugin/icore.cpp

@@ -563,7 +563,6 @@ void ICore::openFiles(const QStringList &arguments, ICore::OpenFilesFlags flags)
     m_mainwindow->openFiles(arguments, flags);
 }
 
-
 /*!
     \fn ICore::addCloseCoreListener
 
@@ -580,6 +579,20 @@ void ICore::addPreCloseListener(const std::function<bool ()> &listener)
     m_mainwindow->addPreCloseListener(listener);
 }
 
+QString ICore::systemInformation()
+{
+    QString result = PluginManager::instance()->systemInformation() + '\n';
+    result += versionString() + '\n';
+    result += buildCompatibilityString() + '\n';
+#ifdef IDE_REVISION
+    result += "From revision %1\n").arg(QString::fromLatin1(Constants::IDE_REVISION_STR).left(10));
+#endif
+#ifdef QTC_SHOW_BUILD_DATE
+     result += "Built on %1 %2\n").arg(QLatin1String(__DATE__), QLatin1String(__TIME__));
+#endif
+     return result;
+}
+
 void ICore::saveSettings()
 {
     emit m_instance->saveSettingsRequested();