Add option to select which messages are sent when you add participant to event

[Urpokarhu1]

Hello,

Add an option to select which messages are sent when you add participant to event, at the moment face to face sends both emails (notification email+ical email) to the added user.

[danmarsden]

Hi there - thanks for the report, typically feature development or improvements like this are only completed if someone funds the development or sends us a pull request. Feel free to reach out privately if you would like to fund any improvements!