Buddies will now be seen as stars in the chat

People might not know all the flags

+ Added the ability to see the account age of registered users. Changes
are both in server and client. The server will now send back the
registration date along with the user data. The client will then use
this to calculate the account age and display it in the user details
window.

context menu for a message sender's name in chat; also display the user level icon next to the name; minor consistency and type-safety changes