Fixed Generator for Hiearchical Specific stimuli

- Fix: new Generator for Hierarchical population code, using corrected EM mixture model.
- Fix: corrected Hierarchical launcher to put num_repetition on last dimension, to make it compatible with multiple reruns.
Reloader for Mixed specific stimuli, fixed EM

- Fix: Reloader for mixed population on specific stimuli. Using new runs with fixed EM fits. Gives better results, need more repetitions now.
Plots Cosyne 2013

- Added: Plots for Cosyne 2013. Unpublished.