STYLE: Remove unused include directory
STYLE: Remove unused include directory

The GraphTheory directory does not exist.

dawnsong/ANTs,stnava/ANTs,dawnsong/ANTs,stnava/ANTs,stnava/ANTs,dawnsong/ANTs,stnava/ANTs,dawnsong/ANTs,dawnsong/ANTs,stnava/ANTs,dawnsong/ANTs,dawnsong/ANTs,stnava/ANTs,stnava/ANTs