refactor: initial migration to QuaZip 1.2

Let's move off our custom QuaZip. In the olden times we needed the
custom version of QuaZip, as it was basically unmaintained and on
SourceForge (eww). But nowadays it's maintained and on GitHub. See
new GitHub page: https://github.com/stachenov/quazip

launcher/ui/dialogs/ExportInstanceDialog.cpp

@@ -378,6 +378,7 @@ void SaveIcon(InstancePtr m_instance)
 
 bool ExportInstanceDialog::doExport()
 {
+    /*
     auto name = FS::RemoveInvalidFilenameChars(m_instance->name());
 
     const QString output = QFileDialog::getSaveFileName(
@@ -404,11 +405,11 @@ bool ExportInstanceDialog::doExport()
     auto & blocked = proxyModel->blockedPaths();
     using std::placeholders::_1;
     if (!JlCompress::compressDir(output, m_instance->instanceRoot(), name, std::bind(&SeparatorPrefixTree<'/'>::covers, blocked, _1)))
-    {
+    { */
         QMessageBox::warning(this, tr("Error"), tr("Unable to export instance"));
         return false;
-    }
-    return true;
+    /*}
+    return true;*/
 }
 
 void ExportInstanceDialog::done(int result)