Buffered Streaming

Major refactoring of the code as we moved from a "full download" model to a "buffered streaming" model. Items are divided into fixed-size chunks, and users only fetch enough to fill a viewing buffer, requesting more as they finish watching the previous ones. However, this makes the simulation much more computationally intensive. The division of items into chunk can be disabled by setting the chunk-size parameter to 0.

Globecom'13 release

First public release of the simulator, solely for the purpose of uploading it to Zenodo.
The simulator is still in its potentially unsafe beta state, but at this stage I doubt I am going to do any significant work on it in the foreseeable future, so I'm giving it a 1.0.0 tag. If there's any interest in this I will add some documentation, in the meanwhile contact me for any doubt or query.