Updated FAQ (markdown)

FAQ.md

@@ -1,22 +1,22 @@
-### A. Installation
+### Installation
  1. [Cannot enter flash mode](#A1)
  2. [Flashing issues](#A2)
  3. [Firmware update with file upload not working](Upgrading#upgrade-by-file-upload)
  4. [Device is hot! or There was white smoke!](#A4)
  5. [Sonoff 4CH V2 / Sonoff Dual V2 won't flash](#A5)
  6. [Flashing fails on MacOS High Sierra](#A6)
-### B. Wi-Fi
+### Wi-Fi
  1. [Cannot connect to Wi-Fi](#B1)
  2. [Entered wrong Wi-Fi information](#B2)
  3. [Device often reconnects to Wi-Fi](#B3)
  4. [Wi-Fi stops working](#B4)
  4. [Control device from outside my network](https://github.com/arendst/Sonoff-Tasmota/issues/5352)
-### C. MQTT
+### MQTT
  1. [Cannot connect to my MQTT broker](#C1)
  2. [Frequent MQTT reconnects](#C2)
  3. [What's Topic, GroupTopic and FallBack Topic](https://github.com/arendst/Sonoff-Tasmota/wiki/Tips#topic-grouptopic-and-fallback-topic)
 
-### D. Device
+### Device
  1. [How do I configure this unknown device](Configuration-Procedure-for-New-Devices)
  2. [Relay clicks/LED flashes at 1 sec interval](#D2)
  3. [Status LED blinking](#D3)