Added a few more videos to presentations (#3102)
Added a few more videos to presentations (#3102)

* Added a few more videos to presentations

* added duration to presentations

* Update presentations.rst

blaze/dask,mrocklin/dask,dask/dask,jakirkham/dask,dask/dask,mrocklin/dask,ContinuumIO/dask,jakirkham/dask,jcrist/dask,blaze/dask,ContinuumIO/dask,jcrist/dask