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/app/wifimanage/State.cpp

@@ -6,12 +6,16 @@ namespace tt::app::wifimanage {
 void State::setScanning(bool isScanning) {
     tt_check(mutex.acquire(TtWaitForever) == TtStatusOk);
     scanning = isScanning;
+    scannedAfterRadioOn |= isScanning;
     tt_check(mutex.release() == TtStatusOk);
 }
 
 void State::setRadioState(service::wifi::WifiRadioState state) {
     tt_check(mutex.acquire(TtWaitForever) == TtStatusOk);
     radioState = state;
+    if (radioState == service::wifi::WIFI_RADIO_OFF) {
+        scannedAfterRadioOn = false;
+    }
     tt_check(mutex.release() == TtStatusOk);
 }