Generalized Minimum Label Spanning Tree Problem datasets

=== File format
Each line in the files has the format A,B,C where A is the start vertex of the
specified edge, B is the end vertex of the specified edge, and C is the label
associated with that edge, with A < B (because graphs are symmetric for the
CTSP). Both vertex indices and labels are 1-indexed (aka numbering starts
from 1). Every file has a label on the first line that should be ignored in
parsing the file.

=== Files
The files SW_*_*_*_*.txt are the Small-World problem instances. The numbers in
the filename, in order, are:
- Number of vertices
- Density
- Number of labels
- Random seed

The files TSP_*_*_*_*.txt are the TSPLib-based problem instances. The values
in the filename, in order, are:
- Number of vertices
- Density
- Number of labels
- LC, LR, RC, or RR, the generation technique described in the paper.
