Add compile-time 'warning' with FastLED version number.  Bumped to 2.1.1
Add compile-time 'warning' with FastLED version number.  Bumped to 2.1.1

MiketheChap/FastLED,neographophobic/FastLED,PaulStoffregen/FastLED,wsilverio/FastLED,remspoor/FastLED,felixLam/FastLED,kcouck/FastLED,yaneexy/FastLED,MiketheChap/FastLED,FastLED/FastLED,PaulStoffregen/FastLED,remspoor/FastLED,corbinstreehouse/FastLED,liyanage/FastLED,ryankenney/FastLED,NicoHood/FastLED,wsilverio/FastLED,FastLED/FastLED,tullo-x86/FastLED,neographophobic/FastLED,MattDurr/FastLED,corbinstreehouse/FastLED,NicoHood/FastLED,FastLED/FastLED,felixLam/FastLED,wilhelmryan/FastLED,FastLED/FastLED,liyanage/FastLED,MattDurr/FastLED,ryankenney/FastLED,tullo-x86/FastLED,eshkrab/FastLED-esp32,eshkrab/FastLED-esp32,wilhelmryan/FastLED,yaneexy/FastLED,kcouck/FastLED,PaulStoffregen/FastLED