Do not use makefiles from libStatGen #73
Description
I have a version of libStatGen that I've already built, but bamUtil is insisting on using the makefiles from libStatGen and building everything all over again, which is obviously less than ideal, especially for a package manager. Could you create an option in the Makefile for bamutil so that I can simply point to the LIB/INCLUDE files for libStatGen, and it thereby doesn't need to clone that repo and use its makefiles?