- This program is released with GPLv3+ license.
- build: ~$ ./configure && make && make install
- default install dir is set to "(configure_dir)/install" 
- if you needs, make symlink /usr/bin/shunit to (configure_dir)/install/.../shunit
  or set PATH to (configure_dir)/install/.../shunit
  shell automatically resolves the self-exist dirpath.
