fixed timing bug in htlm-plugin

It was just a typo.

bug fix other "

bug missing "

Merge pull request jspsych#60 from jodeleeuw/dev

update to v3.1

Merge pull request jspsych#59 from jodeleeuw/css

Css

Update README.md

make sure unprocessed functions get preserved in trial obj

related to issue jspsych#42

Remove normalize trial variables method

This is a bad idea for this plugin, since check_fn is a function. Need to figure out a way to protect variables like this one. For now, just revert to no functions as trial variables for this plugin.

change default option for choices parameter

Update README.md