Add detection progress bar to the user interface

ResourceManager.h

@@ -34,6 +34,8 @@ public:
     
     void RegisterDeviceListChangeCallback(ResourceManagerCallback new_callback, void * new_callback_arg);
 
+    unsigned int GetDetectionPercent();
+
     void DeviceListChanged();
 
     void DetectDevices();
@@ -43,6 +45,8 @@ public:
 private:
     static std::unique_ptr<ResourceManager>     instance;
 
+    unsigned int                                detection_percent;
+
     std::vector<i2c_smbus_interface*>           busses;
     std::vector<RGBController*>                 rgb_controllers;
     std::vector<DeviceDetectorFunction>         device_detectors;