Get the current unsettled offers. This can include offers in all statuses.
API GROUP : BETTING_READ
|open||The offer is available to be matched by other users.|
|cancelled||The offer has been cancelled by the user.|
|edited||The offer has been edited by the user but is still available to be matched by other users with the new values.|
|matched||The offer has been fully matched by one or more other users.|
|flushed||The offer has been flushed by the system and is no longer available to be matched by other users.|