Graph size reduction?

[Luke-Poeppel]

Only connect the 20-25% of closest nodes in the complete extractions. It's pretty silly that it's a completely connected graph (nearly, b.c. no overlaps). For big datasets like Essen/MC, it's still prohibitively slow when, say, ~5000 fragments are found.

Specification:
Add bound_distance_percentage argument to build_graph.

[Luke-Poeppel]

I tangentially mention this "future-work" strategy in the paper. Might be cool to finally do it if/when I get reviews back.