No Error Message for bad trial name in task->trialOrders

[jspjut]

If a task refers to a trial name that doesn't exist, when initializing that session, FPSci will crash without a useful error message.

Minimal reproduction, put something like this in a session:

            tasks = (
                {
                    id = "task1";
                    count = 7; 
                    trialOrders = [
                        { order = ["go"]; },
                    ];
                },
            );
            trials = ( 
                { 
                    // id = "go";
                    targetIds = ( "staticFrontWallGo" ); 
                },
            ); 

If the trial id is uncommented, this should load and run fine, but without the name in the trial, FPSci will crash when trying to load the trial into the task order. The same happens if the trial has a name, but the name in the trialOrders list is wrong.