make configure && 64 bit indices


I was looking where was defined the type idx_t and found that I have to manually modify a file (metis.h) to change to 64 bit indices... Am I right?
If so, I would suggest to modify the "Makefile" to add this as a configuration parameter when one do a "make config". Moreover, with a default value, users won't be bothered by an obligation to manage this new parameter.