Bugfix: Submit/Cancel order scripting errors + Ordermanager GetOrder & CancelOrder improvements (#584)

* Fixes Submit and Cancel order functions for scripting. Adds tests to ensure that wrapper functions actually execute as expected. Adds more coverage. Fixes a few other tests

* Fixes issues

* Simplifies tests

* Update cancel order to properly cancel an order. Adds example script. Adds sweet tests.

* Fixes bad test setup for cancelling orders

* Adds new order manager GetOrderInfo function to call the wrapper function and then store it in the order manager

* Addresses order concerns

* LOWERS THE CASE OF ALL EXCHANGE NAMES BECAUSE ORDER MANAGER NEVER CARED ABOUT CASING OR YOUR FAMILY

* Removes asset and currency requirement from cancelling orders via validation test

* Fixes old cancel order assumptions that had requirements for currency and asset

* Moves all the logs and events to the dedicated Cancel function instead of exclusively doing it in CancelAllOrders

* Adds more detail logging. Fixes lbank fee test

* Addresses comms manager issues

* Removes go routine for pushing events. Better to let them fail

engine/rpcserver.go

@@ -811,7 +811,7 @@ func (s *RPCServer) GetOrder(_ context.Context, r *gctrpc.GetOrderRequest) (*gct
 		Quote:     currency.NewCode(r.Pair.Quote),
 	}
 
-	result, err := exch.GetOrderInfo(r.OrderId, pair, "") // assetType will be implemented in the future
+	result, err := s.OrderManager.GetOrderInfo(r.Exchange, r.OrderId, pair, "") // assetType will be implemented in the future
 	if err != nil {
 		return nil, fmt.Errorf("error whilst trying to retrieve info for order %s: %s", r.OrderId, err)
 	}