SLI requires the following utilities (and their dependencies) to operate:
- rsync,
- a GUI to ask the SSH password (SSH_ASKPASS environment variable must be set).

Attention, SLI use the CMake construction system. So, the installation
procedure is:
1) extract the archive containing the program sources,
2) enter the directory containing the sources,
3) run the command `cmake .'
	(or `cmake -DCMAKE_INSTALL_PREFIX = / usr .' to install the
	package under `/usr' instead of `/usr/local' ),
4) run the command `make',
5) run the command `make install'
	(or `make install DESTDIR=absolute_path_to_somedir' to place the files
	in a temporary location instead of the expected one).
