Files:
	run_insert - Shell script that loops over the 24 sections, running insertor.py for each one
	insertor.py - Python script to insert the structure for a section
	structure/ - Folder with the structure to insert, one file per section

Running:
	$ ./run_insert <source directory> <output directory>

	The source directory is where the original Penn Treebank is stored.
	e.g. /corpora/TreeBank3/parsed/mrg/wsj/