Adding a program generating test data.

The program that generate this gen.c produces
a set of rules to be loaded to load/load2
file system interace of smacke. Or to be used
as input file for smackload.

The count of differents labels (option l=N) and of
different access rights (option r=N) can be specified.
The count of rules produced to the ouput can also
be specified (option o=N). By default, l=5, r=100 and o=500.

The generated labels are made of 4 to 7 random letters.
The standard C function 'rand' is used without seeding it;
what means that same options produces same results.

Signed-off-by: José Bollo <jose.bollo@open.eurogiciel.org>