Gets the contact's display name. Script: http://www.wlmessenger.net/api/3.7/loader.js
The display name can be used by applications to render a contact to the application user. The display name is computed based on the available properties for a contact, including the Nickname, ApplicationDisplayName, DisplayName, and Address.
If DisplayNameMode is set to FullName then DisplayName will return the FirstName and LastName in the appropriate order based on the market of the signed-in user. This will fall back to using DisplayName if FirstName and LastName are not set.
To render emoticons contained within the display name as images, an application should consider using EmoticonEncode(String).