allow for text and data to be non-arrays for single trial block
allow for text and data to be non-arrays for single trial block

issue #24
adrianoesch/jsPsych,wolfgangwalther/jsPsych,jspsych/jsPsych,jspsych/jsPsych,andyh616/jsPsych,jspsych/jsPsych,Scienthusiast/jsPsych,shamrt/jsPsych,jspsych/jsPsych,shamrt/jsPsych,adrianoesch/jsPsych,msrresearch/jsPsych,andyh616/jsPsych,vergenzt/jsPsych,erikasf/jsPsych,wolfgangwalther/jsPsych,vergenzt/jsPsych,Scienthusiast/jsPsych,erikasf/jsPsych,jodeleeuw/jsPsych