[WIP] Add Sensecounts

[oxinabox]

WordNet includes files giving the counts of each wordsense in Semcor. This PR makes them accessible. It is pretty useful information for WSD.

It does increase the load time of WordNet some.

It is WIP, since I've not yet written any documentation for it. Nor have I written any tests.

[jbn]

I haven't use the Semcor stuff. Interesting. Thanks for the WIP :)

[oxinabox]

Sense Counts are practically required for WSD tasks, because of their highly unbalanced nature.

I should really finish this PR off. I've been using it for almost 2 months, without having made the tests portable.

[aviks]

bump?

[oxinabox]

I am not going to finish this. Someone else could reasonably do so, but this is very low priority for me.