Facebook Request Dialog is used to invite friends to start using an application, or to send request
for some specific action to application users. It is implemented as button and link on which user has
to click to open the request dialog. There is also an option to open it automatically on page load.
For all details about the control, with descriptions of all optional properties, please visit:
Facebook Invite All Friends Tutorial.
Note: from the API version 2.0 this control is deprecated