Adapted the old files from cs222.

It's a mess.

Also, some initial data - the senate looks good with eps=0.1 and
k = 2, which is better than predicted by our model.
The reason is that the bound is too conservative.
For eps=0.01 the community structure gets absorbed in the noise though.

Included a draft of the paper, containing the description of the
algorithm and the some bounds. Experimentation provided some
new insight into possible ways to analyze the utility guarantees.