Be less reliant on internal chat

[alepez]

Our chat is very simple and should only be used for the first contact. It exists to protect our users privacy, so their contact information are secret. Users should be encouraged to use more structured chats, on which we don't have control, like telegram or discord.

How to encourage people using other chats:

• [ ] show an info box in the "Chat with " page, promoting the use of other chats
• [ ] implement the "Friend" feature #111
• [ ] show a "Add Friend" button in the "Chat with " and "Public profile" page
• [ ] show alternative way of contact someone (only if friend, info are available in protected data #110)