Add fields for Social profile urls

[craigS89]

Checklist

• I made sure that there are no existing issues - open or closed - to which I could contribute my information.
• I made sure that there are no existing discussions - open or closed - to which I could contribute my information.
• I have read the FAQs inside the app (Menu -> About -> FAQs) and my problem isn't listed.
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• This issue contains only one feature request.
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Feature description

Would it be possible to add fields showing entries for the SOCIALPROFILE format from the vCard 4.0 standard?

Perhaps in a similar layout to how th IMPP fields are displayed.

Why do you want this feature?

I'm finding this an ever more important piece of data to store for a contact and now often social media profile are the main avenue of contacting people.
It would be nice if this was shown on the contact card.

Additional information

A lot of vcard 3.0 services back port this using X-SOCIALPROFILE