Added Documentation directory, and markdown version of 'Introducing Ensembles' blog post.
Added Documentation directory, and markdown version of 'Introducing Ensembles' blog post.

realmacsoftware/ensembles,drewmccormack/ensembles,realmacsoftware/ensembles,ChronicStim/ensembles,drewmccormack/ensembles,ChronicStim/ensembles