Feature request: Groups can have social links, telephone and email

[felixwatts]

Sometimes its appropriate for a group to have social links, a telephone number or an email address. Not all groups are primarily managed on Hylo. Some already have a presence on other platforms and it would be useful to be able to model that properly.

Our Hylo use case is mainly as a directory of other organizations. Most of those already have a web presence and aren't interested in migrating to Hylo, but we'd still like to list them and provide a way to contact them within our Hylo group.

Currently the workaround is to add the social links and contact details to the Purpose Statement or Description.