Provide some basic tools (in cpp but probably others too)

[tbarbette]

I think those software are useful in bash scripts and could be included in the VMs:

• bc (so one can play with grading in floating points)
• killall (kill processes without playing with pids around)
• find (find some patterns in the student code)
• expect (limit pipe problems)

Not sure about the procedure... But thanks for considering this :)

[mpiraux]

which could be one more