ccanlint: check all headers for examples.

pushpull module doesn't have examples in pushpull.h.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
ccanlint: offer to insert license comments where they're missing.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
pushpull: new module.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
cdump: new module.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
cdump: handle , at end of enums.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
cdump: add useful tool to generate enum name string table.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
io: fix example in io_plan.h which didn't compile.

This was found because ccanlint now looks for examples here too.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>