add an example for build asdf with dependence

Hi Daniel, Recently I was taking a part time job that use ECL to call some lisp code in C and I looked "Embed ECL in Qt" in ECL Quarter. The author suggest to load a library with other asdf library dependences in C++ we need to first create a dummy empty static or shared library and then load the "fasb" file contains actual library with all dependences. He said directly the ECL's asdf:make-build to make shared or static library with dependences are broken at the time write. But I found now it's no problem to do so, maybe you have fixed that part? Also he made a mistake that asdf:make-build will not include unused library, for example, quicklisp and even asdf when bundle a library or executable, I tested via (print (find-package :ql)) in the code need to build, and it returns nil, so we don't need to run ecl with no rc to build the library. As we're most likely to build lisp library, static or dynamic with dependence in C, and this is not given example in ECL manual, so I write a small example for doing that maybe helpful to other ECL users.

-- Sincerely, Bo