* Optimize WiFi strength indicator
- Simplify `WifiGetRssiAsQuality`
- Make WiFi strength indicator in web status line color independent
- Correct count of visible bars in strength indicator
- Save flash space (64 bytes; with WiFi status line 80 bytes)
- Highlight connected SSID/AP in settings with compiler option `USE_HIGHLIGHT_CONNECTED_AP` (needs additional 256 bytes)
* Change format of RSSI display