$pdo
$pdo : \PDO
An interface to the contact table in the database
getClient() : \client
Get the client that this contact is linked to
The client
delete() : boolean
Remove this contact from the database
If this doesn't succeed (i.e. false is returned), that means the contact was removed manually or by another instance of this class
If something went wrong with the database
True on success, false on failure
createOffer() : \offer
Make a new offer for this contact
If something went wrong with the database
If there was a problem with the input
A new instance of the offer class containing the new offer