fix #81

As it was found the issue has been caused by parallel access to
QGraphicsScene so it has been cleared before convertion to pixmap. It
has been resolved by deletion concurrent updates in this place (it makes
sense anyway).

sources/awesome-widget/plugin/awkeys.cpp

@@ -229,10 +229,9 @@ void AWKeys::reinitKeys(const QStringList currentKeys)
 
 void AWKeys::updateTextData()
 {
-    QFuture<QString> text = QtConcurrent::run(m_threadPool, [this]() {
-        calculateValues();
-        return parsePattern(keyOperator->pattern());
-    });
+    // do not do it in parallel to avoid race condition
+    calculateValues();
+    QString text = parsePattern(keyOperator->pattern());
 
     emit(needTextToBeUpdated(text));
     emit(dataAggregator->updateData(values));