Add a progress bar to the ResultsSetFromFile

[drvinceknight]

We have a progress bar for the actual play of the tournaments and for the analysis of the results (once the interactions have been read in to memory). This is good as it gives feedback (especially for very large tournaments when you might not know for sure that everything is actually running).

When redoing some of the plots for the paper, I read in the whole tournament data and was left with a long time with no user feedback: we don't have a progress bar for the reading of the data from file.

Have almost finished implementing a solution for this (one that includes the possibility of quickly reading the size of the data before actually reading it in). Just got to write a couple of tests and make sure it's all doing what it's supposed to do but here's a screenshot: