Shellscript that will take an URL of a source .tar.gz (or other)
file, and perform some steps to generate a package: 

 - setup a basic Makefile
 - run "make fetch" and "make makesum"
 - generate a dummy pkg/PLIST
 - run "make extract"
 - try to find out the WRKSRC (if needed)
 - try to find out of this package uses GNU auto-configure
