SITE_EMAIL_SEND	SITE Endpoint
	/rpc/site/?method=SITE_EMAIL_SEND
	This method is identical to MESSAGING_EMAIL_SEND, with the restriction that you can only access objects created in the current session etc
	You will also need to set up a messaging account, using SETUP_MESSAGING_ACCOUNT_MANAGE, that matches the &fromemail and has &siteemail=Y.