src/toolcontext: Provide contract options
src/toolcontext: Provide contract options

`--no-contract` option to disable the contracts usage
`--full-contract` option to enable the contracts usage in all classes

Signed-off-by: Florian Deljarry <947961b90cb93a9343e8ca0457b9d463c3e20c1c@gmail.com>

privat/nit,privat/nit,privat/nit,privat/nit,privat/nit,privat/nit,privat/nit,privat/nit,privat/nit,privat/nit