Now SimpleDemo2 works (* & 3 rules have high probs for toy_3n)
Added y axis labels to graph_samples, also added internal  function.
Merged SimpleDemo2 & SimpleDemo; now we can enter parameters when calling SimpleDemo.run() in ipython notebook.
Improved VectorSummary.graph_samples y-axis labeling; added 'complex_grammer'.
Merge branch 'master' of https://github.com/piantado/LOTlib
merging stuff from Steve's commit