Fixes and improvements (#132)

- Fix glitch when turning on WiFi: It would temporarily show "No networks found" right before starting the first scan.
- Fix spinner to use Assets.h
- Replace statusbar battery icons 
- Better statusbar icon for when WiFi is on but not connected
- Replace statusbar WiFi icons and Wifi Manage RSSI/lock icons
- Fix for crash when timer is null in I2cScanner
- Deprecate Spacer
- Fixes for toolbar layout (simplified)
- Improved ImageViewer app: center image and add filename text on the bottom
- Add LV debug params to sdkconfig.developer
- Disabled LV spinner, msgbox and window widgets. These have equivalents in Tactility.

Tactility/Source/lvgl/Statusbar.cpp

@@ -90,8 +90,6 @@ static void statusbar_destructor(TT_UNUSED const lv_obj_class_t* class_p, lv_obj
 
 static void update_icon(lv_obj_t* image, const StatusbarIcon* icon) {
     if (icon->image != nullptr && icon->visible && icon->claimed) {
-        lv_obj_set_style_image_recolor(image, lv_color_white(), 0);
-        lv_obj_set_style_image_recolor_opa(image, 255, 0);
         lv_image_set_src(image, icon->image);
         lv_obj_remove_flag(image, LV_OBJ_FLAG_HIDDEN);
     } else {