Allow sending event invites

[alcinnz]

Problem

Often you want to coordinate times & places (online or off) at which to meet other people you can contact online, typically via eMail.

Usually this need can be addressed using WebMail, but I'd prefer to stick with the native apps where I can. And besides, I recently found myself in a situation where I was wanting to use an account which didn't include webmail.

Proposal

elementary Mail + elementary Calendar can already be used as-is to accept iCal invites & add them to your calendar.

I propose that a button be added to the "Participants" tab of the add/edit event dialog which opens Mail (or another email client) to prepare an eMail describing the event & attaching an iCal invite. The user may then edit this mail before sending it.

Prior Art (Optional)

Most webmail clients including GMail+Google Calendar, or FastMail, includes such a feature. In which case RSVP features are common where links are provided to indicate whether or not the invitee can make that time/place. I cannot expect elementary Mail + Calendar to include this RSVP feature without adding a server component.

So do integrated email/calendar/contacts clients like Thunderbird. Though I think this can be implemented without the tight coupling found there.