Removed forced event handler for custom types.
Removed forced event handler for custom types.

Allow adding custom types in alpha models and consuming there.
AlexCatarino/Lean,jameschch/Lean,JKarathiya/Lean,JKarathiya/Lean,StefanoRaggi/Lean,Jay-Jay-D/LeanSTP,StefanoRaggi/Lean,AlexCatarino/Lean,AlexCatarino/Lean,StefanoRaggi/Lean,Jay-Jay-D/LeanSTP,jameschch/Lean,jameschch/Lean,JKarathiya/Lean,Jay-Jay-D/LeanSTP,QuantConnect/Lean,QuantConnect/Lean,QuantConnect/Lean,QuantConnect/Lean,StefanoRaggi/Lean,StefanoRaggi/Lean,Jay-Jay-D/LeanSTP,jameschch/Lean,AlexCatarino/Lean,Jay-Jay-D/LeanSTP,JKarathiya/Lean,jameschch/Lean