gauche: new package

Gauche is an R7RS Scheme implementation developed to be a handy script
interpreter, which allows programmers and systemadministrators to write
small to large scripts for their daily chores. Quick startup, built-in
system interface, native multilingual support are some of its goals.

Signed-off-by: Hiroshi Kawashima <kei-k@ca2.so-net.ne.jp>
Reviewed-by: Vicente Olivert Riera <Vincent.Riera@imgtec.com>
Tested-by: Vicente Olivert Riera <Vincent.Riera@imgtec.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>