Alter code structure && change room list filtering mechanics && add

sorting && init categoriy for rooms.

src/imageproviderconnection.cpp

@@ -0,0 +1,6 @@
+#include "imageproviderconnection.h"
+
+ImageProviderConnection::ImageProviderConnection(QObject* parent)
+    : QObject(parent) {}
+
+ImageProviderConnection::~ImageProviderConnection() {}