[SYS][BREAKING] Add gateway states, Offline mode and refactor sleep (#2020)

Gaterway states to improve LED management
Make the sleep function accessible outside BT
BREAKING remove sleep for ESP8266
BREAKING lowpowermode API changed to powermode and new mode definition

Co-authored-by: Florian <1technophile@users.noreply.github.com>

prod_env.ini.example

@@ -77,7 +77,7 @@ build_flags =
   '-DMQTT_USER="lolin-esp32"'
   '-DMQTT_PASS="abcdefghi"'
   '-DMQTT_SERVER="192.168.1.17"'
-  '-DDEFAULT_LOW_POWER_MODE=2'
+  '-DDEFAULT_LOW_POWER_MODE=INTERVAL'
 
 ;hacked Sonoff RF-Bridge
 [env:sonoff-rfbridge-hacked]