Sick of waiting for make to traverse all of those directories
when you only modified one little file? Well, enough of that nonsense!
Doing "make quicky=dir" (e.g. "make quicky=source/blender/src")
goes to that directory, compiles the stuff in there (and the
subdirectories), then instantly links blender afterwards.
Also has support for more than one directory using quotes, e.g.,
1 dir: make quicky=source/blender/src
2 dirs: make quicky="source/blender/src source/blender/blenkernel"